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disaster pants

American  
[diz-as-ter pants] / dɪzˈæs tər ˌpænts /

noun

Slang.
  1. (used with a plural verb) sudden gastric distress and especially diarrhea caused by a change in diet.

    The smoothies are supposed to burn fat and raise energy levels, but they gave me disaster pants.


Etymology

Origin of disaster pants

First recorded in 2010–15