breach vs blunder

breach and blunder both are nouns.

Word	Noun	Adjective	Verb	Adverb
breach	Yes	No	Yes	No
blunder	Yes	No	Yes	No

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

breach (noun)	blunder (noun)
a failure to perform some promised act or obligation	an embarrassing mistake
a personal or social separation (as between opposing factions)
an opening (especially a gap in a dike or fortification)

breach (verb)	blunder (verb)
make an opening or gap in	utter impulsively
act in disregard of laws, rules, contracts, or promises	make one's way clumsily or blindly
	commit a faux pas or a fault or make a serious mistake