boarding vs departure

boarding and departure both are nouns.

Word	Noun	Adjective	Verb	Adverb
boarding	Yes	No	No	No
departure	Yes	No	No	No

As nouns, departure is a hypernym of boarding; that is, departure is a word with a broader meaning than boarding:

Other hypernyms of boarding include going, going away, leaving.

boarding (noun)	departure (noun)
the act of passengers and crew getting aboard a ship or aircraft	the act of departing
a structure of boards	euphemistic expressions for death
	a variation that deviates from the standard or norm