back out
US /bæk aʊt/
UK /bæk aʊt/

1.
desistir, voltar atrás
to withdraw from a commitment or agreement
:
•
He promised to help, but then he backed out at the last minute.
Ele prometeu ajudar, mas depois desistiu no último minuto.
•
She decided to back out of the deal because of the high risks involved.
Ela decidiu desistir do negócio por causa dos altos riscos envolvidos.