Meaning of bad trip

bad' trip'

Pronunciation: [key]
— Slang. Slang.
  1. a mentally or physically horrifying drug-taking experience, as one accompanied by nightmarish hallucinations or by physical pain.
  2. a dismayingly unpleasant experience: He was so ill-prepared that college was a bad trip for him.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.