foul-up vs blunder

foul-up and blunder both are nouns.

Word	Noun	Adjective	Verb	Adverb
foul-up	Yes	No	No	No
blunder	Yes	No	Yes	No

As nouns, foul-up and blunder are synonyms defined as:

Other synonyms of foul-up include bloomer, blooper, boner, boo-boo, botch, bungle, flub, fuckup, pratfall.

foul-up (noun)	blunder (noun)
an embarrassing mistake	an embarrassing mistake

foul-up (verb)	blunder (verb)
	utter impulsively
	make one's way clumsily or blindly
	commit a faux pas or a fault or make a serious mistake