'cool off' definitions:

Definition of 'cool off'

(from WordNet)
verb
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." [syn: calm, calm down, cool off, chill out, simmer down, settle down, cool it]
verb
Lose intensity; "His enthusiasm cooled considerably" [syn: cool, cool off, cool down]
verb
Feel less enamoured of something or somebody

Synonyms of 'cool off'

From: Moby Thesaurus