When looking for antonyms for the phrase "are pertinent," one could consider words such as irrelevant, immaterial, and inappropriate. These words convey meanings that are contrary to the concept of being relevant, applicable or fitting. Something that is irrelevant goes against the context, while something immaterial may not be deemed relevant. Inappropriate goes against standards of what is suitable or fitting. It's crucial to understand both the meaning of the word you're searching antonyms for and the meaning attached to the antonyms themselves, to recognize the adequate context and appropriate word selection.