At least one word and a gloss are required to form a valid synset. Pointers entered following all the words in a synset represent semantic relations between all the words in the source and target synsets. Adjective may be organized into clusters containing one or more head synsets and optional satellite synsets. Each adjective cluster is enclosed in square brackets, and may have one or more parts. Each part consists of a head synset and optional satellite synsets that are conceptually similar to the head synset's meaning.
Most adjective clusters contain two antonymous parts.
They use the basic synset syntax. Comments can be entered in a lexicographer file by enclosing the text of the comment in parentheses. This is often used by the lexicographers to verify the syntax of files under development or to leave a note to oneself while working on entries. A synset must have at least one word, and the words of a synset must appear after the opening brace and before any other synset constructs. See Special Adjective Syntax for a description of adjective clusters and markers.