A thesaurus provides a standard language or set of terms with which to describe a subject area. Applied to indexing of a database, it indicates to a searcher which terms to use to retrieve the maximum number of relevant documents.

The thesaurus terms are used by indexers to describe the contents of publications in a consistent, comprehensive and concise manner. These terms are listed in the Descriptors field (DE=) of each record added to the database.

Using our interactive Thesaurus Search you can browse for terms via a hierarchical, alphabetical, or rotated index display. These display formats allow you to navigate the thesaurus alphabetically or through the hierarchical relationships between terms. After finding appropriate terms, you can submit a search for those terms in the database descriptor field.

Each term may be followed by:

• Notes: These comments provide additional information about the term, eg, definitions and usage history.
• Broader Terms and Narrower Terms: These labels reflect the hierarchical nature of the descriptors, eg, DISEASES is a broad term relative to FISH DISEASES.
• Related Terms: These are non-hierarchical relations that direct the users to alternative descriptors in the event that the initial term is conceptually inappropriate or there is a need to broaden the search.
• Use For Terms: These are non-descriptor terms for which the main term should be used instead. Use For and Use terms always go together and this relationship is used in a variety of situations, such as when to use synonyms or near synonyms, eg, USE Artificial Lakes FOR Man-made lakes.