oneiromancy vs divination

oneiromancy and divination both are nouns.

Word	Noun	Adjective	Verb	Adverb
oneiromancy	Yes	No	No	No
divination	Yes	No	No	No

As nouns, divination is a hypernym of oneiromancy; that is, divination is a word with a broader meaning than oneiromancy:

oneiromancy: divination through the interpretation of dreams
divination: the art or gift of prophecy (or the pretense of prophecy) by supernatural means

Other hypernyms of oneiromancy include foretelling, fortune telling, soothsaying.

oneiromancy (noun)	divination (noun)
divination through the interpretation of dreams	the art or gift of prophecy (or the pretense of prophecy) by supernatural means
	a prediction uttered under divine inspiration
	successful conjecture by unusual insight or good luck