thesaurus
Thesaurus.
Synonyms.
thesaurus is the answer!
Typically, a thesaurus will have both synonyms and antonyms that you can look for.
Some synonyms for agitator are disruptor, dissident, malcontent, anarchist, advocate. Some antonyms for agitator are conciliator, peacemaker, conservative, moderate, arbitrator.
Synonyms and antonyms are things that are similar or opposite. Synonyms of hot would be could be hot or balmy. Hot or balmy would mean something similar to hot. Antonyms of hot would be cold or chilly. Hot or chilly would mean something the opposite of hot.
Slow and leisurely would be synonyms.
A good website for synonyms and antonyms would be www.synonym.comOr you can type www.antonym.comOr you can type www.definition.com
A thesaurus specifically would typically provide lists of synonyms and antonyms for words, while a dictionary would focus on providing definitions, pronunciation, and word usage in addition to synonyms and antonyms.
Examples would be unconstitutional attempts at governance such as a legislative veto or judicial activism("legislating from the bench").
Antonyms would have opposite meanings. Since huge and gigantic have very similar meanings they are synonyms.
Synonyms are words that mean the same or almost the same thing. Some synonyms for the word "numerous" would be: many, a lot of, several. Antonyms are words that are opposites. Some antonyms for the word "numerous" would be: few, little, a handful of.