In-apposite is a word that refers to something that is not suitable or relevant to a particular situation. The term means something that is not congruous, appropriate, or pertinent. To express the opposite of this word, one can use a variety of antonyms that convey a contrasting idea. Some of these include relevant, suitable, appropriate, fitting, harmonious, congruent, and appropriate. On the other hand, some synonyms for in-apposite are alien, inappropriate, conflicting, discordant, and unsocial. Antonyms can be quite useful when we want to communicate the opposite of a specific word or idea, and they help us to convey our thoughts and feelings clearly and concisely.