Antonyms are words that have opposite meanings to each other. For instance, "clean" is the antonym of "mess," as "clean" suggests orderliness, tidiness, and organization, while "mess" pertains to disarray, confusion, and disorder. Similarly, "whole" is the antonym of "halves," as "whole" refers to a complete unit, while "halves" signify partial units or parts of a whole. Antonyms are useful in communication, as they help to distinguish ideas and concepts that are different from one another. Hence, it is essential to know antonyms, synonyms, and related words for effective communication and expression.