It also references discontinued terms from the former Descriptor Authority File, which are used for accessing information prior to 1986. Associated term relationships are displayed under each Main Term. Each of these elements of the Thesaurus display is explained below. Main Terms Main Terms appear in boldface letters. Main Term descriptors are limited to 60 characters.
Punctuation is used minimally.
Hypens are used where needed for clarity. In cases where ambiguity may occur, and to distinguish the meaning of homographs, Main Terms and Use reference terms appear with qualifying expressions in parentheses. Descriptor Codes are seven-character, alphanumeric authority numbers for Thesaurus terms. New Descriptor Codes have been assigned to all Main Terms. Since a Descriptor Code is a unique number representing a specific Main Term, it may be used in online searching as an alternative to specifying the Main Term itself.