1.
If you ~ a form or other document requesting information, you write information in the spaces on it. (mainly AM; in BRIT, usually use fill in )
Fill out the application carefully, and keep copies of it.
= fill in
PHRASAL VERB: V P n (not pron), also V n P
2.
If a fairly thin person fills out, they become fatter.
A girl may ~ before she reaches her full height.
PHRASAL VERB: V P