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LCH (Library of Congress Subject Headings) - Synopsis

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The Library of Congress Subject Headings (LCSH) were developed and are maintained by the U.S. Library of Congress (LOC).

LCSH is a controlled vocabulary used for indexing, cataloging, and searching for bibliographic records in library catalogs and electronic databases.

LCSH covers a wide range of topics, including history, politics, geography, law, economics, and genealogy.

Metathesaurus Scope
The Metathesaurus representation of LCS\H includes approximately 6,500 biomedical and health-related terms from the Library of Congress Subject Headings, Twelfth Edition. It does not include any hierarchies or relationships.

LCSH is used by indexers, subject catalogers, online searchers, and in electronic retrieval systems.

Update Frequency
LCSH is updated weekly.

Metathesaurus Update Frequency
LCSH was last updated in the Metathesaurus in 1992.

Sites Consulted

  1. Jefferson's Legacy: A Brief History of the Library of Congress – The Collections [Internet]. Washington (DC): Library of Congress; 2006 Mar 27 [cited 2010 Mar 30]. Available from: