adjective
calmer; -est
not angry, upset, excited, etc.
used to describe weather that is not windy, stormy, etc.
noun
a quiet and peaceful state or condition [noncount]
[count] :a peaceful mental or emotional state - usually singular
the calm before the storm
verb
calms; calmed; calming
to become or to cause (someone) to become less upset, emotional, excited, etc. [+ obj]
+ down
to become or to cause (something) to become less active, violent, forceful, etc. [no obj]
usually + down
US