Are Antonyms in a Thesaurus?

Antonyms are listed alphabetically, just as synonyms are. They appear as boldface headwords at their own alphabetical places in the thesaurus only if they are part of a synonym group elsewhere.

Does a thesaurus have antonyms?

A thesaurus does not give the meaning of words. A thesaurus does not always include antonyms. The plural of thesaurus is "thesauri" or "thesauruses".

What's the antonym for antonym?

The opposite of antonym is synonym, which is a word that has the same meaning as another word.