rat on
US /ræt ɑːn/
UK /ræt ɑːn/

1.
melaporkan, mengadu
to inform on someone, especially to an authority
:
•
He threatened to rat on his friends if they didn't help him.
Dia mengancam akan melaporkan teman-temannya jika mereka tidak membantunya.
•
She decided not to rat on her brother, even though he broke the rules.
Dia memutuskan untuk tidak melaporkan kakaknya, meskipun dia melanggar aturan.