boyish
adjective
[ ˈbɔɪɪʃ ]
• of, like, or characteristic of a male child or young man.
• "his boyish charm"
Similar:
youthful,
young,
childlike,
adolescent,
teenage,
teenaged,
fresh-faced,
immature,
juvenile,
infantile,
childish,
babyish,
callow,
green,
puerile,
bread-and-butter,