big mouth

US /ˈbɪɡ ˌmaʊθ/
UK /ˈbɪɡ ˌmaʊθ/
"big mouth" picture
1.

болтун, сплетник

a person who talks too much, especially about things that should be kept secret

:
Don't tell him your secret; he's a real big mouth.
Не рассказывай ему свой секрет; он настоящий болтун.
Her brother is such a big mouth, he always spills the beans.
Ее брат такой болтун, он всегда все выбалтывает.