arithmancy vs divination

arithmancy and divination both are nouns.

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

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

arithmancy: divination by means of numbers
divination: the art or gift of prophecy (or the pretense of prophecy) by supernatural means

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

arithmancy (noun)	divination (noun)
divination by means of numbers	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