nih-gov/www.nlm.nih.gov/research/umls/new_users/glossary.html
2025-02-26 13:17:41 -05:00

431 lines
33 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!doctype html>
<html lang="en">
<head>
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"/>
<link rel="preconnect" href="https://fonts.googleapis.com">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
<link href="https://fonts.googleapis.com/css2?family=Roboto:wght@100;300;400;500;700&display=swap" rel="stylesheet">
<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.0.10/css/all.css" integrity="sha384-+d0P83n9kaQMCwj8F4RJB66tzIwOKmrdb46+porD/OvrJ+37WqIM7UoBtwHO6Nlg" crossorigin="anonymous">
<link rel="schema.DC" href="http://purl.org/dc/elements/1.1/" title="The Dublin Core metadata Element Set" />
<script src="https://assets.nlm.nih.gov/uswds/js/uswds-init.min.js"></script>
<link rel="stylesheet" href="/home_assets/uswds/css/styles.css">
<title>UMLS - Glossary</title>
<link rel="schema.DC" href="http://purl.org/dc/elements/1.1/" title="The Dublin Core metadata Element Set" />
<meta name="DC.Title" content="UMLS Glossary" />
<meta name="DC.Publisher" content="U.S. National Library of Medicine" />
<meta name="DC.Date.Issued" content="2009-01-13" />
<meta name="DC.Date.Modified" content="2012-08-15" />
<meta name="NLMDC.Date.LastReviewed" content="2016-07-29" />
<meta name="NLM.Contact.Email" content="nlmumlscustserv@mail.nlm.nih.gov" />
<meta name="DC.Type" content="Training Material and Manuals" />
<meta name="NLM.Permanence.Level" content="Permanence Not Guaranteed" />
<meta name="DC.Rights" content="Public Domain" />
<meta name="DC.Language" content="eng" />
<meta name="keywords" content="Unified Medical Language System, UMLS" />
<meta name="description" content="The UMLS integrates and distributes key terminology, classification and coding standards, and associated resources to promote creation of more effective and interoperable biomedical information systems and services, including electronic health records. " />
<!-- Google Tag Manager --><script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push(
{'gtm.start': new Date().getTime(),event:'gtm.js'}
);var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-MT6MLL');</script>
<!-- End Google Tag Manager -->
</head>
<body>
<!-- Google Tag Manager -->
<noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-MT6MLL" height="0" width="0" style="display:none;visibility:hidden" title="googletagmanager"></iframe></noscript>
<!-- End Google Tag Manager -->
<!-- TOP NAV -->
<a class="usa-skipnav" href="#main">Skip to main content</a>
<div class="usa-banner site-banner" aria-label="Official government website">
<div class="usa-accordion">
<header class="usa-banner__header">
<div class="usa-banner__inner">
<div class="grid-col-auto"> <img class="usa-banner__header-flag" src="https://assets.nlm.nih.gov/uswds/img/us_flag_small.png" alt="U.S. flag"/> </div>
<div class="grid-col-fill tablet:grid-col-auto">
<p class="usa-banner__header-text"> An official website of the United States government </p>
<p class="usa-banner__header-action" aria-hidden="true"> Heres how you know </p>
</div>
<button class="usa-accordion__button usa-banner__button" aria-expanded="false" aria-controls="gov-banner"> <span class="usa-banner__button-text">Heres how you know</span> </button>
</div>
</header>
<div class="usa-banner__content usa-accordion__content" id="gov-banner">
<div class="grid-row grid-gap-lg">
<div class="usa-banner__guidance tablet:grid-col-6"> <img class="usa-banner__icon usa-media-block__img" src="https://assets.nlm.nih.gov/uswds/img/icon-dot-gov.svg" role="img" alt="" aria-hidden="true"/>
<div class="usa-media-block__body">
<p> <strong> Official websites use .gov </strong> <br />
A <strong>.gov</strong> website belongs to an official government
organization in the United States. </p>
</div>
</div>
<div class="usa-banner__guidance tablet:grid-col-6"> <img class="usa-banner__icon usa-media-block__img" src="https://assets.nlm.nih.gov/uswds/img/icon-https.svg" role="img" alt="" aria-hidden="true"/>
<div class="usa-media-block__body">
<p> <strong> Secure .gov websites use HTTPS </strong> <br />
A <strong>lock</strong> ( <span class="icon-lock">
<svg xmlns="http://www.w3.org/2000/svg" width="52" height="64" viewBox="0 0 52 64" class="usa-banner__lock-image" role="img" aria-labelledby="banner-lock-title-default banner-lock-description-default" focusable="false">
<title id="banner-lock-title-default">Lock</title>
<desc id="banner-lock-description-default">A locked padlock</desc>
<path fill="#000000" fill-rule="evenodd" d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z"/>
</svg>
</span> ) or <strong>https://</strong> means youve safely connected to the .gov website. Share sensitive information only on official, secure websites. </p>
</div>
</div>
</div>
</div>
</div>
</div>
<!-- HEADER -->
<header id="siteheader" class="usa-header usa-header--basic">
<div class="usa-nav-container tablet:padding-x-4 mobile-lg:padding-x-2 padding-y-1">
<div class="grid-row padding-y-105">
<div class="grid-col-8 desktop:grid-col-4 tablet-lg:grid-col-4 tablet:grid-col-6"> <a href="https://www.nlm.nih.gov/"> <img src="https://assets.nlm.nih.gov/uswds/img/NLM_White.png" alt="NLM logo" class="logo margin-top-1"> </a> </div>
<div class="desktop:grid-col-4 desktop:grid-offset-4 tablet-lg:grid-col-6 tablet-lg:grid-offset-2 tablet:grid-col-6 grid-col-12">
<form class="usa-search desktop:margin-top-2 tablet:margin-top-2 mobile:margin-top-1" role="search" data-gtm-form-interact-id="0" method="get" action="//vsearch.nlm.nih.gov/vivisimo/cgi-bin/query-meta" target="_self" name="searchForm" id="searchForm2">
<input class="usa-input ui-autocomplete-input" aria-label="Search" type="search" name="query" data-gtm-form-interact-field-id="0" id="search2" autocomplete="off" placeholder="Search NLM" >
<input type="hidden" name="v:project" value="nlm-main-website">
<button class="usa-button border border-top border-bottom border-right border-white" role="button" aria-label="Search" type="submit"> <span class="usa-search__submit-text"> <i class="fas fa-search"></i> </span> </button>
</form>
</div>
</div>
</div>
</header>
<div class="bg-secondary insertCOOP">
<div class="usa-nav-container">
<div class="usa-navbar ">
<button class="usa-menu-btn">Menu</button>
</div>
<nav aria-label="Primary navigation" class="usa-nav">
<button class="usa-nav__close"><img src="https://assets.nlm.nih.gov/uswds/img/close.svg" alt="close"></button>
<ul class="usa-nav__primary usa-accordion insertNav">
<li class="usa-nav__primary-item desktop-lg:margin-x-5 desktop:margin-x-3 tablet:margin-x-0">
<button type="button" class="usa-accordion__button usa-nav__link usa-current" aria-expanded="false" aria-controls="basic-nav-section-one"> <span>Products and Services <i class="fas fa-caret-down margin-left-05"></i> </span> </button>
<ul id="basic-nav-section-one" class="usa-nav__submenu bg-secondary" hidden="">
<li class="usa-nav__submenu-item"> <a href="//eresources.nlm.nih.gov/nlm_eresources/"><span>All Products and Services</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//clinicaltrials.gov/"><span>ClinicalTrials.gov</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//collections.nlm.nih.gov/"><span>Digital Collections</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//catalog.nlm.nih.gov"><span>LocatorPlus Catalog</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//meshb.nlm.nih.gov/search"><span>Medical Subject Headings (MeSH)</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//medlineplus.gov/"><span>MedlinePlus</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//pubmed.ncbi.nlm.nih.gov/"><span>PubMed/MEDLINE</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//uts.nlm.nih.gov/uts/"><span>Unified Medical Language System (UMLS)</span></a> </li>
</ul>
</li>
<li class="usa-nav__primary-item desktop-lg:margin-x-5 desktop:margin-x-3 tablet:margin-x-0">
<button type="button" class="usa-accordion__button usa-nav__link usa-current" aria-expanded="false" aria-controls="basic-nav-section-two"> <span> Resources for You <i class="fas fa-caret-down margin-left-05"></i></span> </button>
<ul id="basic-nav-section-two" class="usa-nav__submenu bg-secondary" hidden="">
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/portals/researchers.html"><span>For Researchers</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/portals/publishers.html "><span>For Publishers</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="ttps://www.nlm.nih.gov/portals/librarians.html"><span>For Librarians</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/training.html "><span>For Educators/Trainers </span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/portals/healthcare.html"><span>For Health care Professionals</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//www.nlm.nih.gov/portals/public.html "><span>For the Public</span></a> </li>
</ul>
</li>
<li class="usa-nav__primary-item desktop-lg:margin-x-5 desktop:margin-x-3 tablet:margin-x-0">
<button type="button" class="usa-accordion__button usa-nav__link usa-current" aria-expanded="false" aria-controls="basic-nav-section-three"> <span>Explore NLM <i class="fas fa-caret-down margin-left-05"></i> </span> </button>
<ul id="basic-nav-section-three" class="usa-nav__submenu bg-secondary" hidden="">
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/about/index.html"><span>About the Library</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/about/visitor.html"><span>Visit the Library</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/hmd/index.html"><span>History of Medicine</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/about/org.html"><span>NLM by Organization</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/news/newsandevents.html"><span>News, Events, and Updates</span></a> </li>
</ul>
</li>
<li class="usa-nav__primary-item desktop-lg:margin-x-5 desktop:margin-x-3 tablet:margin-x-0">
<button type="button" class="usa-accordion__button usa-nav__link usa-current" aria-expanded="false" aria-controls="basic-nav-section-four"> <span> Grants and Research <i class="fas fa-caret-down margin-left-05"></i> </span> </button>
<ul id="basic-nav-section-four" class="usa-nav__submenu bg-secondary" hidden="">
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/ep/index.html"><span>NLM Extramural Programs</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.nlm.nih.gov/research/index.html"><span>NLM Intramural Research Program</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="https://www.ncbi.nlm.nih.gov/"><span>National Center for Biotechnology Information</span></a> </li>
<li class="usa-nav__submenu-item"> <a href="//lhncbc.nlm.nih.gov/"><span>Lister Hill National Center for Biomedical Communications</span></a> </li>
</ul>
</li>
</ul>
</nav>
</div>
</div>
<!-- End of TOP NAV -->
<!-- DIVISIONAL BANNER -->
<div class="bg-gray-70">
<div class="grid-container">
<div class="grid-row divisional">
<div class="grid-col text-white">
<div class="float-left">
<h4 class="margin-bottom-0">Unified Medical Language System<small><sup>&reg;</sup></small> (UMLS<small><sup>&reg;</sup></small>)</h4>
</div>
<div class="float-right margin-top-05">
<p>
<a class="text-white" href="/research/umls/quickstart.html">UMLS Quick Start Guide</a>
&nbsp;&nbsp;|&nbsp;&nbsp;<a class="text-white" href="/research/umls/faq_main.html">FAQs</a>
&nbsp;&nbsp;|&nbsp;&nbsp;<a class="text-white" href="/research/umls/support.html">Customer Support</a>
</p>
</div>
</div>
</div>
</div>
</div>
<!--END DIVISIONAL BANNER -->
<!-- Breadcrumbs -->
<div class="grid-container">
<nav class="usa-breadcrumb usa-breadcrumb--wrap padding-top-1" aria-label="Breadcrumbs">
<ol class="usa-breadcrumb__list">
<li class="usa-breadcrumb__list-item"> <a href="/index.html" class="usa-breadcrumb__link"><span>Home</span></a> </li>
<li class="usa-breadcrumb__list-item"> <a href="/healthit" class="usa-breadcrumb__link"><span>Health IT</span></a> </li>
<li class="usa-breadcrumb__list-item"> <a href="/research/umls/" class="usa-breadcrumb__link"><span>UMLS</span></a> </li>
<li class="usa-breadcrumb__list-item"> <span>Glossary</span></li>
</ol>
</nav>
</div>
<!-- End Breadcrumbs -->
<main class="padding-bottom-5" id="main">
<div class="grid-container">
<div class="grid-row">
<div class="col">
<div class="h1">UMLS Glossary</div>
</div>
</div>
<!--UMLS Glossary -->
<p><a class="bottomnav" href="#a">A</a> B <a class="bottomnav" href="#c">C</a> D E <a class="bottomnav" href="#f">F</a> G <a class="bottomnav" href="#h">H</a> I J <a class="bottomnav" href="#k">K</a> <a class="bottomnav" href="#l">L</a> <a class="bottomnav" href="#m">M</a> N <a class="bottomnav" href="#o">O</a> <a class="bottomnav" href="#p">P</a> Q <a class="bottomnav" href="#r">R</a> <a class="bottomnav" href="#s">S</a> <a class="bottomnav" href="#t">T</a> <a class="bottomnav" href="#u">U</a> <a class="bottomnav" href="#v">V</a> W X Y Z</p>
<p><strong><a id="a" name="a"></a>-A-</strong></p>
<p>Atom - The smallest unit of naming in a source, viz, a specific string with specific code values and identifiers from a specific source. As such, they can be thought of as representing a single meaning with a source Atoms are the units&nbsp;of terminology that come from sources and form the building blocks of the concepts in the Metathesaurus.</p>
<p>AUI- Atom Unique Identifier.&nbsp; An identifier for the atom in the UMLS.&nbsp; It is the primary key to the concepts table.</p>
<p>Back to the top.</p>
<p><strong><a id="c" name="c"></a>-C-</strong></p>
<p>Cluster - A cluster is data in the Metathesaurus grouped by the same type of identifier (CUI, CODE, SDUI, SCUI). Users can search for and view Metathesaurus data using clusters in the MetamorphoSys RRF Browser.</p>
<p>Code - A short value (typically numeric but often also including letters) used to identify a particular member of a particular group of objects (such as atoms, strings or concepts). In all capitals, or when referring to atoms, CODE refers to the value of the field in the Metathesaurus, and is what the Metathesaurus perceives as the most useful identifier that each source assigns to its atoms. In some special cases, the CODE values are assigned by the NLM.&nbsp; In that case, the values are preceded with MTH.</p>
<p>Concept - The fundamental unit of meaning in the Metathesaurus. A concept represents a single meaning and contains all atoms from any source that express that meaning in any way, whether formal or casual, verbose or abbreviated. All of the atoms within a concept are synonymous. Each concept is assigned at least one semantic type.&nbsp; Every concept is assigned a Concept Unique Identifier, or CUI, which uniquely identifies that single meaning.</p>
<p>Concept Name &ndash; A string chosen to represent the concept as a whole. The name is selected from the atoms belonging to the concept according to a simple priority list (the term whose source/term type is highest on the list is chosen, with a special procedure for choosing between two source/term type values that are identical.) The priority list may be altered by users as they wish, thus changing the concept names.</p>
<p>Context - The indicators of meaning of a term that are not explicitly expressed in the term itself. Such indicators may include an appearance in a hierarchy, the siblings in that hierarchy, the intention of the source providers for the use of the source, or be implicit in an anaphoric or elliptical expression.&nbsp; In the Metathesaurus, the hierarchical contexts of parent, child, and sibling are represented explicitly.</p>
<p>Co-occurrence - The simultaneous appearance of two different Metathesaurus concepts with representatives from the same source appear in the same piece of information, whether journal article, abstract, or other publication or database.&nbsp; It is a co-occurrence because two different concepts are occurring together in a third-party source.&nbsp; The frequency with which two concepts co-occur may be used as an indication of their relatedness.&nbsp; The Metathesaurus includes the co-occurrence frequencies of concepts in certain databases.&nbsp; The most notable of the co-occurrences are the MEDLINE co-occurrences, which represent co-occurrences of MeSH descriptors in MEDLINE citations.</p>
<p>CUI - The Concept Unique Identifier for a Metathesaurus concept to which strings with the same meaning are linked. One of the principles of the Metathesaurus is that meanings should be preserved over time regardless of what terms (atoms) are used to express those meanings. The CUI is an identifier that uniquely represents a meaning and (ideally) over time the meaning of a CUI does not change. &nbsp;As sources are updated and as Metathesaurus editors discover errors or find that the meanings of terms have shifted over time, the meaning corresponding to a CUI may be altered (merged or split) or may disappear.&nbsp; In such cases, the changes in the meaning of the CUIs involved are tracked in the CUI history table, so that any CUI from any previous release of the Metathesaurus may always be mapped to the equivalent concept in the current Metathesaurus (if any) or may be identified as having been deleted (in which case the closest similar concept will often be specified).</p>
<p>Content View - A specific subset of the Metathesaurus which includes specific entities within the Metathesaurus identified as potentially useful in a particular setting for a defined purpose.&nbsp; For example the Natural Language Processing Content View identifies terms that are useful for Natural Language Processing.</p>
<p>CVF - Content View Flag, a binary tag used to identify in which of the content views of the Metathesaurus an entity (relationship, attribute, or atom) is a member.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="f" name="f"></a>-F-</strong></p>
<p>Filters - An function in MetamorphoSys that, when enabled, removes information. For example, when the "Languages to Remove" filter is set to exclude French, all French language terms are removed.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="h" name="h"></a>-H-</strong></p>
<p>Hierarchy - A graded series, often described as a tree. These source-asserted multi-level organization of a source vocabulary may be different between vocabularies designed for different purposes.</p>
<p>&nbsp;<a href="#">Back to the top.</a></p>
<p><strong><a id="k" name="k"></a>-K-</strong></p>
<p>Knowledge Sources - The three main parts of the UMLS: The Metathesaurus, Semantic Network, and the Specialist Lexicon, with is associated Lexical Tools.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="l" name="l"></a>-L-</strong></p>
<p>Lexical Variants - Different forms of a word or phrase.&nbsp; Types of variant include verb tenses, singular and plural forms, and variations in punctuation, capitalization, and word order. For example treats, treating, and treated are all language variants of the verb "treat". &nbsp;</p>
<p>Lexical Tools - A suite of computer programs that can be used in a variety of ways to process text. The Lexical Tools make use of the Specialist Lexicon, one of the three Knowledge Sources of the UMLS.</p>
<p>Lexicon - An collection, usually alphabetical, of the words in a language and information about them (e.g., their definitions).</p>
<p>Log file - A file containing information about the processing of a computer program. Both MetamorphoSys and the MRCXT Builder produce log files.</p>
<p>LUI - Lexical Unique Identifier.&nbsp; The unique identifier of a term in the Metathesaurus.&nbsp; Terms are different from strings in that they group together strings that are lexical variants of one another.&nbsp; For example, the strings 'Eye', 'eye', and 'eyes' all have different SUIs, but share the same LUI.&nbsp; LUIs are not generally maintained over time, as their generation depends on the algorithms used in the Lexical Variant Generator program, which may change from time to time.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="m" name="m"></a>-M-</strong></p>
<p>Machine readable files - Files that are formatted in such a way that they are easily imported into a computer program or database.</p>
<p>Mapping - A mapping provides links from entities in one source to entities in another terminology. Entities may be terms, codes, concepts, descriptors or expressions.</p>
<p>MetamorphoSys - The program distributed with the UMLS used to install, customize, and view Metathesaurus data.</p>
<p>Metathesaurus &nbsp;- One of the three UMLS Knowledge Sources; a collection of multiple vocabularies, code sets, and standards.</p>
<p>Morphology - Word formation information such as inflection, derivation, and compounding.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="o" name="o"></a>-O-</strong></p>
<p>Orthography - The aspect of grammar study that deals with letters and spelling. &nbsp;</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="p" name="p"></a>-P-</strong></p>
<p>Pipe-delimited data - A format for information in which data is separated into sections by a "|" character. The UMLS knowledge source files are all delivered as Pipe-delimited data.</p>
<p>Precedence &nbsp;- Priority; status in order of importance. The Metathesaurus provides a precedence ranking of its constituents sources and their term types, which is used to determine which term is the Preferred Term.</p>
<p>Preferred term - The string preferred in a source or in the Metathesaurus as the name of a concept, lexical variant, or string.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="r" name="r"></a>-R-</strong></p>
<p>Raw data/Raw data view &nbsp;- The data files of the UMLS in machine readable format (normally pipe-delimited data) before being altered with a computer application. &nbsp;</p>
<p>Root Source Abbreviation (RSAB) - An NLM-assigned source abbreviation stripped of its version information. For example, the RSAB for 2012 version of the Current Procedural Terminology is CPT. The purpose of the stripped source is to have a source value that can be preserved across versions of the metathesaurus. CPT will identify CPT2011 in one version and CPT2012 in a later version, for example.</p>
<p>RxNorm - A standardized nomenclature for clinical drugs produced by the National Library of Medicine. &nbsp;</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="s" name="s"></a>-S-</strong></p>
<p>SCUI - Source Concept Unique Identifier. The source-asserted unique identifier for each source concept.</p>
<p>SDUI - Source&nbsp;Descriptor Unique Identifier. The source-asserted unique identifier for each source descriptor.</p>
<p>Semantic Groups - A small set of groups into which all semantic types are aggregated. Semantic groups provide a very broad view of Metathesaurus concepts through their assigned semantic types. Semantic groups&nbsp; are not included in the UMLS distribution but can be accessed through the Semantic Network Website [http://semanticnetwork.nlm.nih.gov/SemGroups/].</p>
<p>Semantic Network - One of the three UMLS Knowledge Sources; it provides a broad categorization of all concepts represented in the UMLS Metathesaurus.</p>
<p>Semantic relationships - Links between categories (semantic types) in the Semantic Network, the most basic relationship is 'isa', for example &lsquo;Amphibian isa Animal.&rsquo; &nbsp;The relationships can be thought of as naming relationships which may potentially exist between members of those categories.</p>
<p>Semantic Type - One of the broad categories (for example, "Clinical Drug" or "Disease or Syndrome") described in the UMLS Semantic Network.&nbsp; One or more semantic types is assigned to each Metathesaurus concept.</p>
<p>Source - A terminology intended for use in computer systems, and controlled and maintained by an authority, the source provider.&nbsp; In some cases, the source may be a portion of a richer source of information, with the keys to that information provided by the names in the source. The Metathesaurus collects many source terminologies and integrates them into a unified concept structure.</p>
<p>Source Concept - A source concept is a source asserted-collection of atoms that are considered to be synonymous.</p>
<p>Source Descriptor - A source descriptor is a source asserted-collection of concepts (or atoms if there is no concept level organization) that are considered to be closely related (but not necessarily synonymous).</p>
<p>Source transparency - The idea that one should be able to extract vocabularies and code sets from the UMLS Metathesaurus and from that data, reproduce the original vocabulary or code set.</p>
<p>Source vocabularies - see Source. The vocabularies, code sets, and data standards that are contained in the UMLS Metathesaurus. &nbsp;</p>
<p>Specialist Lexicon - One of the three UMLS Knowledge Sources; an English lexicon containing common and biomedical terms with their syntactic, morphological, and orthographic information.</p>
<p>String - A particular sequence of characters forming a word or phrase in a particular language (e.g., English or Spanish).&nbsp; The character set used as the basis for this sequence is UNICODE UTF-8. Any difference in upper or lower case, word order, punctuation, or other form would indicate a separate string.&nbsp; In the Metathesaurus, when the same sequence occurs in different languages, each is considered to be a separate string and receives a different string identifier (SUI). Thus, "Color", "color" and "Colors" are 3 separate English Strings, and the Spanish word "color" is a fourth.</p>
<p>Subset - A portion (or set) of the data in the UMLS Metathesaurus. MetamorphoSys may be used to generate customized subsets.</p>
<p>SUI - The unique identifier for each unique string in the Metathesaurus. Strings that differ in any way, e.g., by upper or lower case, will have different SUIs.</p>
<p>Suppressibilty - In the UMLS Metathesaurus terms can be marked as "suppressible", these terms can then be removed from the subset. These terms are most often identified as suppressible because of ambiguity in meaning or lack of face validity.</p>
<p>Synonym - A string which can be substituted for another in every expression without changing the meaning of the expression. In practice, the Metathesaurus considers atoms synonymous if it is thought that the vast majority of experts in the field would not consider any differences between the objects to which they refer to be of significance.&nbsp;</p>
<p>Syntax &nbsp;- The way linguistic elements (words) are used together to form constituents (phrases or clauses).</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="t" name="t"></a>-T-</strong></p>
<p>Term - A word &nbsp;or collection of words comprising an expression.&nbsp; In the Metathesaurus, a term is the class of all strings that are lexical variants (made singular and normalized to case) of each other. (Eye, eye, eyes = 1 term). . Thus, "Color", "color" and "Colors" would be 3 Strings in the same Term, whereas "Hue" would be a separate term in the same concept. Terms, as recognized computationally in the UMLS environment, are assigned a unique identifier (LUI).</p>
<p>Term type - A value indicating the kind of role an atom plays in its source.&nbsp; Examples include PT for "preferred term," SY for "synonym," and MH for "main heading."&nbsp; Term types are often not assigned by a source, but are assigned in Metathesaurus production, in which case they are usually generic across sources.&nbsp; In some cases, term types may be assigned by the source, are-specific to that particular source.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="u" name="u"></a>-U-</strong></p>
<p>UMLS Terminology Services (UTS) &nbsp;- A computer application that provides internet access to the Knowledge Sources and other related resources made available by developers using the UMLS. The UTS replaces the UMLS Knowledge Source Server (UMLSKS) with new features and improved access to UMLS and other NLM terminology resources.</p>
<p><a href="#">Back to the top.</a></p>
<p><strong><a id="v" name="v"></a>-V-</strong></p>
<p>Versioned Source Abbreviation (VSAB) - A NLM-assigned source abbreviation with accompanying version information. For example, the VSAB for the 2012 version of the Current Procedural Terminology is CPT2012.</p>
<p>&nbsp;</p>
<p class=”margin-top-5”><small>Last Reviewed: July 29, 2016</small></p>
</div>
</main>
<!-- FOOTER -->
<footer class="usa-footer__primary-section padding-top-5 padding-bottom-3 insertfooter">
<div class="grid-container">
<div class="grid-row">
<div class="desktop:grid-col-3 grid-col-6"> <a href="https://www.nlm.nih.gov/socialmedia/index.html">
<p class="text-white">Connect with NLM</p>
</a>
<ul class="social_media add-list-reset">
<li class="margin-right-05"><a href="https://www.facebook.com/nationallibraryofmedicine"><img class="bg-secondary" src="https://www.nlm.nih.gov/images/facebook.svg" alt="Facebook"></a></li>
<li class="margin-right-05"><a title="External link: please review our privacy policy." href="https://www.linkedin.com/company/national-library-of-medicine-nlm/"><img class="bg-secondary" src="//www.nlm.nih.gov/images/linkedin.svg" alt="LinkedIn"></a></li>
<li class="margin-right-05"><a title="External link: please review our privacy policy." href="https://twitter.com/NLM_NIH"><img src="//www.nlm.nih.gov/images/twitter.svg" class="img-fluid bg-secondary" alt="Twitter"></a></li>
<li class="margin-right-05"><a title="External link: please review our privacy policy." href="https://www.youtube.com/user/NLMNIH"><img src="//www.nlm.nih.gov/images/youtube.svg" class="bg-secondary" alt="You Tube"></a></li>
<li class="margin-right-05"><a title="External link: please review our privacy policy." href="https://public.govdelivery.com/accounts/USNLMOCPL/subscriber/new?preferences=true"><img src="//www.nlm.nih.gov/images/mail.svg" class=" bg-secondary" alt="Government Delivery"></a></li>
</ul>
</div>
<div class="desktop:grid-col-3 grid-col-6">
<p class="address_footer text-white"> National Library of Medicine <br>
<a href="https://www.google.com/maps/place/8600+Rockville+Pike,+Bethesda,+MD+20894/@38.9959508,-77.101021,17z/data=!3m1!4b1!4m5!3m4!1s0x89b7c95e25765ddb:0x19156f88b27635b8!8m2!3d38.9959508!4d-77.0988323" class="text-white"> 8600 Rockville Pike <br>
Bethesda, MD 20894 </a></p>
</div>
<div class="desktop:grid-col-3 grid-col-6">
<p><a href="/web_policies.html" class="text-white"> Web Policies </a><br>
<a href="https://www.nih.gov/institutes-nih/nih-office-director/office-communications-public-liaison/freedom-information-act-office" class="text-white"> FOIA </a><br>
<a href="https://www.hhs.gov/vulnerability-disclosure-policy/index.html" class="text-white">HHS Vulnerability Disclosure</a> </p>
</div>
<div class="desktop:grid-col-3 grid-col-6">
<p><a class="supportLink text-white" href="//support.nlm.nih.gov?from="> NLM Support Center </a> <br>
<a href="/accessibility.html" class="text-white"> Accessibility </a><br>
<a href="/careers/careers.html" class="text-white"> Careers </a></p>
</div>
</div>
<div class="grid-row">
<div class="grid-col-12">
<p class="text-center text-white"> <a class="text-white" href="//www.nlm.nih.gov/">NLM</a> | <a class="text-white" href="https://www.nih.gov/">NIH</a> | <a class="text-white" href="https://www.hhs.gov/">HHS</a> | <a class="text-white" href="https://www.usa.gov/">USA.gov</a></p>
</div>
</div>
</div>
</footer>
<script src="//assets.nlm.nih.gov/uswds/js/uswds.min.js"></script>
<script src="//assets.nlm.nih.gov/jquery/jquery-latest.min.js"></script>
<script src="//assets.nlm.nih.gov/jquery/jquery-migrate-latest.min.js"></script>
<script src="/scripts/nlm_autocomplete.js"></script>
<script src="/scripts/nlm_uswds.js"></script>
</body>
</html>