A thesaurus is a vocabulary of controlled subject terms. With controlled terms, search words are standardized, so you don’t have to think of synonyms or different terms for the same concept. A thesaurus is hierarchically structured with broader and narrower terms. You can also use a thesaurus to find additional search terms. Some subject databases include a thesaurus.
In this film you can learn more about how to use controlled subject terms. The film has captions.
