substantiate vs confirm

substantiate and confirm both are verbs.

Word	Noun	Adjective	Verb	Adverb
substantiate	No	No	Yes	No
confirm	No	No	Yes	No

As verbs, substantiate and confirm are synonyms defined as:

substantiate and confirm: establish or strengthen as with new evidence or facts

Other synonyms of substantiate include affirm, corroborate, support, sustain.

substantiate (verb)	confirm (verb)
solidify, firm, or strengthen	make more firm
establish or strengthen as with new evidence or facts	establish or strengthen as with new evidence or facts
make real or concrete; give reality or substance to	strengthen or make more firm
represent in bodily form	administer the rite of confirmation to
	support a person for a position