(US, slang) Engaging in activities typically associated with adulthood. / (nonstandard) Adultery.

present participle of adult

A fully grown human or animal. / A person who has reached the legal age of majority.

Fully grown. / Intended for or restricted to adults rather than children. / Containing material of an explicit sexual nature; of, or pertaining to, pornography. / Vulgar or profane.

(intransitive, informal) To behave like an adult. / (nonstandard, rare) To (cause to) be or become an adult.

plural of adult

Third-person singular simple present indicative form of adult

Third-person singular simple present indicative form of adulter

The state or quality of being an adult.

A predisposition towards adults (or a bias against children or other younger people).