Alcohol and Other Drug Thesaurus - AOD: National Institutes of Health thesaurus. Provides resource for medical, social, and demographic terms related to alcohol and drug use.
Art and Architecture Thesaurus: Getty's terms, as used in several AAT indexes.
Babynames Thesaurus: You can search for a name from its meanings. The site has more than 10,000 names with meanings.
CAS General Subject Vocabulary Helper: Extensive listings for chemistry. Produced by Chemical Abstracts Service, a division of the American Chemical Society.
Concept Space: Management education thesaurus from the London Business School organizes terms into a solar system of related ideas.
Eurodic Autom: European Union terminology. Available on most European Union languages.
Getty Thesaurus of Geographic Names: Structured vocabulary of place names.
Library of Congress Classification Schedules: A comprehensive list of LOC Classification schedules.
Library of Congress Thesauri: Links to multiple LOC thesauri, including GLIN, the Global Legal Information Network.
Maths Thesaurus: Definitions of common mathematical terms, along with broader, narrower, and related concepts.
NASA Thesaurus: National Aeronautics and Space Administration Thesaurus. Extensive coverage of scientific terms.
The Astronomy Thesaurus: Astronomical terms. Searches may be performed in English, French, German, Italian, and Spanish.
Thesaurus of Musical Instruments: Over a thousand instruments, with relational links based on the Library of Congress Subject Headings.