fail vs foul up

fail and foul up both are verbs.

Word	Noun	Adjective	Verb	Adverb
fail	No	No	Yes	No
foul up	No	No	Yes	No

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

fail (verb)	foul up (verb)
stop operating or functioning	make a mess of, destroy or ruin
deteriorate
prove insufficient
disappoint, prove undependable to; abandon, forsake
become bankrupt or insolvent; fail financially and close
be unsuccessful
fail to get a passing grade
fail to do something; leave something undone
judge unacceptable
be unable
fall short in what is expected