Definition of いい大人 (いいおとな)

とな

いい大人

いいおとな

iiotona

expression, noun
(an) adult their age (should, should not, etc.), grown man (woman), person who is old enough (to know better)(oft. used sarcastically)
Other readings:
良い大人【いいおとな】
良い大人【よいおとな】
Related Kanji
large, big
person
good, pleasing, skilled