Meaning of “calm (sb) down” - Learner’s Dictionary

calm (sb) down

phrasal verb with calm uk us /kɑːm/ verb [ T ]

B2 to stop feeling upset, angry, or excited, or to make someone stop feeling this way:

Calm down and tell me what's wrong.

(Definition of “calm (sb) down” from the Cambridge Learner’s Dictionary © Cambridge University Press)