good night
US /ˌɡʊd ˈnaɪt/
UK /ˌɡʊd ˈnaɪt/

1.
buenas noches
used to express good wishes on parting at night, or when someone is going to bed
:
•
She kissed her children and said, "Good night, sleep tight!"
Besó a sus hijos y dijo: "¡Buenas noches, que duerman bien!"
•
He waved and called out, "Good night, everyone!"
Saludó con la mano y gritó: "¡Buenas noches a todos!"