The word "comeoff" has several antonyms, which are words that have opposite meanings. Some of the most commonly used antonyms for "comeoff" include "fail," "lose," "flop," "miss," and "botch." Each of these words implies a lack of success or achievement, and they can be used to describe a variety of situations or contexts. For example, if a company launches a new product that doesn't perform well in the market, it can be said to have "failed" to come off. Similarly, if a sports team loses a game, it can be said to have "missed" its chance to come off as the winner.