bum out

1.  Depress, sadden, dispirit, as in He's been really bummed out since his girlfriend moved to California. [Slang; late 1960s]
2.  Annoy, irritate, vex, as in That haircut will really bum out his parents. [Slang; c. 1970]
3.  Fail badly, as in I got through the midterm, but I bummed out totally on the final exam. This usage is student slang. [Late 1960s]

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1. in. to have a bad experience with drugs. (Drugs.)  I bummed out on angel dust.
2. in. to have any bad experience.  The test was horrible. I bummed out, for sure.

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