expiration vs exhalation

expiration and exhalation both are nouns.

Word	Noun	Adjective	Verb	Adverb
expiration	Yes	No	No	No
exhalation	Yes	No	No	No

As nouns, expiration and exhalation are synonyms defined as:

Other synonyms of expiration include breathing out.

expiration (noun)	exhalation (noun)
the act of expelling air from the lungs	the act of expelling air from the lungs
euphemistic expressions for death	exhaled breath
a coming to an end of a contract period