mistake vs stumble

mistake and stumble both are nouns.

Word	Noun	Adjective	Verb	Adverb
mistake	Yes	No	Yes	No
stumble	Yes	No	Yes	No

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

Other hyponyms of mistake include misremember, slip up, trip up, misjudge, fall for.

mistake (noun)	stumble (noun)
a wrong action attributable to bad judgment or ignorance or inattention	an unsteady uneven gait
an understanding of something that is not correct	an unintentional but embarrassing blunder
part of a statement that is not correct

mistake (verb)	stumble (verb)
to make a mistake or be incorrect	make an error
identify incorrectly	miss a step and fall or nearly fall
	walk unsteadily, tripping repeatedly
	encounter by chance