1
general::
Phrase(s): foul someone or something up
to cause disorder and confusion for someone or something; to tangle up someone or something; to mess someone or something up. • Go away! Don’t foul me up any more. • You’ve fouled up my whole day. • Watch out! You’re going to foul up my kite strings., Phrase(s): foul up
to blunder; to mess up. • Please don’t foul up this time. • The quarterback fouled up in the first quarter, and that lost us the game.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Blunder or cause to blunder; botch, ruin. For example, He's fouled up this report, but I think we can fix it, or Our plans were fouled up by the bad weather. This expression is widely believed to have originated as a euphemism for FUCK UP. [Colloquial; c. 1940]
American Heritage Idioms