definition of
calm down

[1] #1 calm down v. become quiet or calm, especially after a state of agitation; "After the fight both men need to cool off."; "It took a while after the baby was born for things to settle down again.". wn

[2] #2 calm down v. make calm or still; "quiet the dragons of worry and fear". wn

[3] #3 calm down v. become quiet or less intensive; "the fighting lulled for a moment". wn