Meaning of crap up | Babel Free

Definitions

1. To ruin, botch, bungle; to make a mess of.
   idiomatic, mildly, slang, transitive, vulgar
2. To go wrong; to foul up; to make a mistake.
   idiomatic, mildly, slang, vulgar
3. To lie, mislead or give someone bullshit; to tell someone what they want to hear.
   idiomatic, slang

Examples

“This whole thing's his big, bright idea because they don't like having me around crapping up their big, romantic weekends.”

“I really crapped up on my fucking school work, so I had to do that frustrating piece of shit all over again.”

CEFR level