The term "most appetent" refers to someone who has a strong desire or craving for something. To express the opposite, one could use antonyms such as uninterested, indifferent, disinterested, or nonchalant. These words convey a lack of enthusiasm or desire for something. Other antonyms that could be used include satiated, content, fulfilled, or satisfied, which indicate a feeling of completeness, and no longer having a desire for more. While "most appetent" tends to have a positive connotation, the antonyms may have a neutral or negative connotation depending on the context they are used in.