General English

  • adjective smelling or tasting unpleasant
  • adjective very unpleasant
  • noun an action which is against the rules of a game
  • verb to do something to another player which is against the rules of a game

Cars & Driving

  • verb to clog or cover (a sparking plug) with deposits
  • verb to get in the way of or obstruct (another part)


  • adjective immoral, unacceptable. The standard term was appropriated by black street slang as a general indication of disapproval.


  • noun an illegal action against an opposing player, or an action that breaks the rules of a sport
  • verb to act illegally against an opposing player, or break a rule of a sport

Origin & History of “foul”

The underlying meaning of foul is probably ‘rotten, putrid’, with overtones of ‘evil-smelling’. It goes back to an Indo-European *pu-, which may originally have been inspired by the same reaction as produced the English exclamation of disgust at a bad smell, pooh. Amongst its other off-spring were Latin pūs, source of English pus, purulent, and supurate, and Latin putridus, source of English putrid. Its Germanic descendant was *fu-, on which the adjective *fūlaz was based. this produced German faul ‘rotten, lazy’, Dutch vuil ‘dirty’, and English foul, and also the derived noun filth (OE). Defile ‘make dirty’ is not directly related, but its form was influenced by the now obsolete verb befile, which was connected with foul.