Thesaurus.com
Dictionary.com
Definitions

grown-up

[grohn-uhp] / ˈgroʊnˈʌp /
ADJECTIVE
adult
Synonyms
WEAK
developed full-fledged full-grown fully developed grown mature of age
NOUN
adult
Synonyms
WEAK
Mr. Mrs. Ms. gentleman grown person lady mam man miss mister woman
Antonyms
WEAK
child youngster

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.