English → French
youthful /BrE ˈjuːθfʊl, 
ˈjuːθf(ə)l, AmE ˈjuθfəl /
adjective
1 (young) [person, team, population] jeune
2 (typical of youth) [enthusiasm, confusion, freedom] de la jeunesse
his youthful looks or son air jeune
she's very youthful for 65, she's a very youthful 65 elle fait très jeune pour ses 65 ans