agrypnia vs vigil

agrypnia and vigil both are nouns.

Word	Noun	Adjective	Verb	Adverb
agrypnia	Yes	No	No	No
vigil	Yes	No	No	No

As nouns, vigil is a hypernym of agrypnia; that is, vigil is a word with a broader meaning than agrypnia:

agrypnia: a vigil before certain feasts (as e.g. Easter)
vigil: the rite of staying awake for devotional purposes (especially on the eve of a religious festival)

Other hypernyms of agrypnia include watch.

agrypnia (noun)	vigil (noun)
a vigil before certain feasts (as e.g. Easter)	a purposeful surveillance to guard or observe
	the rite of staying awake for devotional purposes (especially on the eve of a religious festival)
	a period of sleeplessness