The purpose of a thesaurus, in information retrieval, is to make it easier to retrieve a maximum number of items that are relevant to your enquiry, and a minimum number of items that are not relevant to your enquiry: to give you more of what you want, and less of what you don’t want.
This thesaurus consists of a list of “preferred terms” and “non-preferred terms” each with an indication of the keyword(s) to be used in indexing. It will also show relations between terms: “broader terms” (BTs), “narrower terms” (NTs) and “related terms” (RTs). Many terms will include “scope notes” (SNs) clarifying their intended use (the subject areas that they cover). Below is a list of the different types of entries that appear in the thesaurus:
SC “subject category” - broad subject area (processes, materials, applications, etc.)
SN “scope note” - explaining the meaning of a term
USE points from non-preferred term to preferred term
UF “used for” - the opposite of USE
UA “use and” - for cases where a concept is expressed by two keywords used together
UFA “used for (and)” - the opposite of UA
NT “narrower term” - the opposite of BT
BT “broader term” - generic-specific, part-whole, etc.
RT “related term” - similar terms, terms in same subject area, opposites
HIS “history” - date added, term(s) used before that date
· Alphabetical listing comprising both preferred and non-preferred terms, together with the terms to which they are related
· Alphabetical listing of keywords, their related terms and what they are used for
· Hierarchical listing of “head terms” with the hierarchies of their narrower terms where they exist
· List of primary terms in English, French and German
· Please note that British English is used in this Thesaurus. There is a list of American spellings and terminology and their British equivalents.
More detailed introduction to the history, structure and use of this thesaurus
Commission VI, Working Group 1 reviews and updated the thesaurus regularly. Contact the Chair of this working unit.