mend vs revamp

mend is a noun but revamp is not a noun.

Word	Noun	Adjective	Verb	Adverb
mend	Yes	No	Yes	No
revamp	No	No	Yes	No

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

mend: restore by replacing a part or putting together what is torn or broken
revamp: provide (a shoe) with a new vamp

mend (noun)	revamp (noun)
the act of putting something in working order again
sewing that repairs a worn or torn hole (especially in a garment)

mend (verb)	revamp (verb)
restore by replacing a part or putting together what is torn or broken	to patch up or renovate; repair or restore
heal or recover	provide (a shoe) with a new vamp