brain fart vs whim

brain fart

noun
  • Something ill-considered and said or done impulsively. 

  • An instance of absent-mindedness or forgetfulness. 

whim

noun
  • A fanciful impulse, or sudden change of idea. 

  • A bird, the Eurasian wigeon. 

  • A large capstan or vertical drum turned by horse power or steam power, for raising ore or water, etc., from mines, or for other purposes 

verb
  • To be seized with a whim; to be capricious. 

How often have the words brain fart and whim occurred in a corpus of books? (source: Google Ngram Viewer )