ˈædʌlt adj. & n. --adj. 1 mature, grown-up. 2 a of or for adults (adult education). b euphem. sexually explicit; indecent (adult films). --n. 1 an adult person. 2 Law a person whohas reached theage of majority. øøadulthood n. adultly adv. [L adultus pastpart. of adolescere growup: cf. ADOLESCENT]