Adult adjectives are listed in this post. Each word below can often be found in front of the noun adult in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing ADULT.
active, additional, aged, american, average, capable, competent, different, early, educated
entire, experienced, female, first, free, full, future, grown, healthy, human
independent, intelligent, legal, little, male, mature, miniature, more, most, new
normal, old, older, only, other, own, positive, quite, rational, real
responsible, sane, second, significant, single, sized, small, strong, successful, supportive
typical, very, vulnerable, young, younger
Hope this word list had the adjective used with adult you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.