The antonyms for the word "prevailing" could include words such as "fading," "passing," or "declining." These words signify a decreasing trend or a diminishing influence, as opposed to the strong and dominant connotation of "prevailing." Another antonym might be "atypical," meaning something that is not representative or characteristic of a prevailing pattern or trend. A more direct antonym could be "defeated" or "overthrown," which signifies a complete opposite of the dominating and triumphing implications of the word "prevailing." In any case, antonyms for "prevailing" help to convey a contrasting idea or concept that is useful in communications and linguistic contexts.