sailor suit
US /ˈseɪ.lər ˌsuːt/
UK /ˈseɪ.lər ˌsuːt/

1.
a child's or woman's dress or suit styled like a sailor's uniform, typically with a square collar and a tie
:
•
The little boy looked adorable in his new sailor suit.
•
She wore a vintage sailor suit to the themed party.