You are here

UMLS Metathesaurus

“The Metathesaurus is a very large, multi-purpose, and multi-lingual vocabulary database that contains information about biomedical and health-related concepts, their various names, and the relationships among them. It is built from the electronic versions of many different thesauri, classifications, code sets, and lists of controlled terms used in patient care, health services billing, public health statistics, indexing and cataloging biomedical literature, and/or basic, clinical, and health services research. In this documentation, these are referred to as the "source vocabularies" of the Metathesaurus. In the Metathesaurus, all the source vocabularies are available in a single, fully-specified database format.” “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.”

General information
Vocabulary type: 
Was vocabulary created as a course project: 
Scope and Usage
“The purpose of NLM's Unified Medical Language System® (UMLS) is to facilitate the development of computer systems that behave as if they "understand" the meaning of the language of biomedicine and health. To that end, NLM produces and distributes the UMLS Knowledge Sources (databases) and associated software tools (programs) for use by system developers in building or enhancing electronic information systems that create, process, retrieve, integrate, and/or aggregate biomedical and health data and information, as well as in informatics research. By design, the UMLS Knowledge Sources are multi-purpose. They are not optimized for particular applications, but can be applied in systems that perform a range of functions involving one or more types of information, e.g., patient records, scientific literature, guidelines, and public health data. The associated UMLS software tools assist developers in customizing or using the UMLS Knowledge Sources for particular purposes. The lexical tools work more effectively in combination with the UMLS Knowledge Sources, but can also be used independently.”
Used By: 
: “NLM and many other institutions apply the UMLS resources in a wide variety of Applications including information retrieval, natural language processing, creation of patient and research data, and the development of enterprise-wide vocabulary services. NLM's applications include PubMed®, the NLM Gateway,, and the Indexing Initiative. Other examples of UMLS-enabled applications include the National Cancer Institutes Enterprise Vocabulary Services and the Agency for Healthcare Research and Quality's National Guidelines Clearinghouse and National Quality Measures Clearinghouse.”
Vocabulary characteristics
Relationship types: 
Vocabulary provider name: 
United States National Library of Medicine
Provider URL: 
Provider section comments: 

"UMLS" is a registered trademark.