Most unacquired is a phrase that typically means not possessing something yet. The antonyms for this phrase can include terms such as gained, acquired, attained or achieved. These words all indicate that something has been acquired, whether it be knowledge, skill, or possession of an object. Another antonym that comes to mind is 'well-educated' as it means having received a good education or training, which is an achievement that one can acquire. One can also use words like skillful or accomplished, which suggest expertise or proficiency in a particular field. Ultimately, the antonyms for "most unacquired" depend on the context in which the phrase is used.