The antonyms for the word "more bonhomous" are simply words that mean the opposite of friendly or amiable. Some synonyms to consider would be hostile, unfriendly, cool, distant, unapproachable, cold, and aloof. These words would describe someone who is not welcoming or personable, someone who does not engage or connect with others. However, it's important to note that some of these words have different connotations depending on the context. For instance, being cool or aloof may be a desirable trait in certain situations, such as in business negotiations or in positions of authority. Ultimately, the antonyms of "more bonhomous" are a diverse group of words that paint a picture of individuals who are either unfriendly or simply reserved.