Some meanings stand in clear opposition. An antonym is a word whose meaning is contrary or complementary to that of another word, such as hot and cold or buy and sell.

Semanticists distinguish gradable antonyms that allow intermediate degrees from complementary pairs that admit no middle, and from relational opposites that name reciprocal roles. Dictionaries and thesauruses list antonyms to support precise choice and vocabulary building.

Not every word has a neat opposite, and culture can shape which contrasts feel natural. Antonymy helps organize semantic fields and supports rhetorical contrast. Children often learn common antonym pairs early as they sort experience into opposing categories.

• Word opposite in meaning to another
• Includes gradable, complementary, and relational types
• Used in dictionaries and teaching
• Structures semantic fields through contrast