smooth down
US /smuːð daʊn/
UK /smuːð daʊn/

1.
2.
calmer, apaiser
to calm or soothe someone, especially after they have been upset or angry
:
•
He tried to smooth down the angry customer.
Il a essayé de calmer le client en colère.
•
Her kind words helped to smooth down the tension in the room.
Ses mots gentils ont aidé à apaiser la tension dans la pièce.