Wiktionary
a. Occurring after a period of adolescence. n. One who has grown out of adolescence.
Usage examples of "postadolescent".
Mitchell, at twenty-eight, looked barely postadolescent, while his grandfather, at sixteen, seemed fully grown and mature.
Many people believe that schizophrenia is a postadolescent occurrence.
I was just going through a stage of postadolescent confusion in which life seems temporarily meaningless and confining.
In my postadolescent, always horny, immature, unabashedly romantic heart of hearts, I hoped that she would speak, that when I turned I would find her there in the trailer doorway, breathtakingly backlit, that she would say-softly, softly-something unimaginably seductive, and that I would take her to bed for a night of unrestrained passion.
The differences, of course, include not just those in the reproductive organs themselves but also all other postadolescent sex-linked differences, such as the differences in beards, body hair, pitch of voice, and breast development.