look up any word, like bukkake:
 
2.
Adjective: A fun personality.
Dude A: My buddy makes cartoons for a living.

Dude B: Yeah?

Dude A: Yup, he has two kids, but he's still young at heart.
by Peacestar August 14, 2011
 
1.
This phrase is different then child like. Young at heart is like still playful still likes to do fun stuff and not have a care in the world. Childlike is just annoying.
She is young at heart.
by 000000001111111 November 04, 2008