Blow chunks
What's the meaning of the phrase 'Blow chunks'?
Vomit.
What's the origin of the phrase 'Blow chunks'?
This expression originated in the USA in the early 1990s. It may have existed as street slang for some time before that. It came to worldwide notice via the popular Wayne's World film in 1992. Wayne [Mike Myers] deserves a commendation for getting three euphemisms for vomit into one sentence:
Garth Algar: Uhm, Wayne? What do you do if every time you see this one incredible woman, you think you're gonna hurl?
Wayne Campbell: I say hurl. If you blow chunks and she comes back, she's yours - but if you spew and she bolts, then it was never meant to be.