Expressions are antonyms if their meanings are opposite. We can distinguish between simple and gradable antonyms.

·         Simple Antonyms

Simple antonyms (or complementaries) “exhaustively divide some conceptual domain into two mutually exclusive compartments” (Cruse, 1986 p. 198). Such antonyms can be weakly defined, but this does not affect the exclusivity of the terms. Some simple antonyms are dead and alive, and true or false.

·         Gradable Antonyms

Gradable antonyms are terms that are opposites, but are not mutually exclusive; there are more than two terms in a domain and these words are gradable along a continuum. The division of the domain into these terms is not mutually exclusive or well-defined (they are relative).  Some examples of these domains are size (enormous, huge, big, average-sized, small, tiny, miniscule), temperature, speed, and weight. These terms can be thought of as being more or less of some property.