An antonym is a word that has the opposite meaning of another. For example:
Bad is an antonym of good.
Coward is an antonym of hero.
However, it's not always the case that one word has just one antonym.
Examples of Antonyms
The following are all antonyms of good:
The first point is that good, like many words, can be a noun or an adjective, so its antonyms will be a mix of nouns and adjectives too. The second point is that antonyms do not have to be exact opposites. There are two main types of antonyms: graded antonyms and complementary antonyms.
Graded antonyms do not have to be opposites of equal weighting. They allow for shades of oppositeness. For example, the following are all antonyms for good:
Complementary antonyms offer no middle ground. With complementary antonyms, each word only has one antonym. (The reason for that is often a relationship between the two words.) For example:
1 / 0
before / after
buy / sell
dead / alive
doctor / patient
husband / wife
man / woman
off / on
predator / prey
yes / no
Adding a Prefix to Form an Antonym
Quite often, an antonym can be made by adding a prefix. For example: