at the back of your mind
US /æt ðə bæk əv jʊər maɪnd/
UK /æt ðə bæk əv jʊər maɪnd/

1.
no fundo da mente, no subconsciente
a thought or worry that you have but that you are not thinking about consciously
:
•
The thought of the upcoming exam was always at the back of her mind.
O pensamento do exame que se aproximava estava sempre no fundo da sua mente.
•
He had a nagging feeling at the back of his mind that he had forgotten something important.
Ele tinha uma sensação incômoda no fundo da sua mente de que havia esquecido algo importante.