verify vs ascertain

verify and ascertain both are verbs.

Word	Noun	Adjective	Verb	Adverb
verify	No	No	Yes	No
ascertain	No	No	Yes	No

As verbs, ascertain is a hyponym of verify; that is, ascertain is a word with a more specific, narrower meaning than verify:

Other hyponyms of verify include check, check off, mark, mark off, tick, tick off, assure, check, control, ensure, insure, see, see to it, check.

verify (verb)	ascertain (verb)
confirm the truth of	be careful or certain to do something; make certain of something
to declare or affirm solemnly and formally as true	learn or discover with certainty
attach or append a legal verification to (a pleading or petition)	find out, learn, or determine with certainty, usually by making an inquiry or other effort
check or regulate (a scientific experiment) by conducting a parallel experiment or comparing with another standard	establish after a calculation, investigation, experiment, survey, or study