corroborate vs back up

corroborate and back up both are verbs.

Word	Noun	Adjective	Verb	Adverb
corroborate	No	No	Yes	No
back up	No	No	Yes	No

As verbs, back up is a hyponym of corroborate; that is, back up is a word with a more specific, narrower meaning than corroborate:

Other hyponyms of corroborate include back, vouch, verify, demonstrate, establish, prove, shew, show, document, validate.

corroborate (verb)	back up (verb)
establish or strengthen as with new evidence or facts	establish as valid or genuine
give evidence for	become or cause to become obstructed
support with evidence or authority or make more certain or confirm	make a copy of (a computer file) especially for storage in another place as a security copy
	move backwards from a certain position
	give moral or psychological support, aid, or courage to