impasse vs turning circle

impasse

noun
  • A road with no exit; a cul-de-sac. 

  • A deadlock or stalemate situation in which no progress can be made. 

turning circle

noun
  • A place where a vehicle can turn and face in the opposite direction. 

  • The path followed by a vessel’s center of gravity when it makes a complete turn of 360° with a consistent rudder angle. (FM 55-501) 

  • The circular path formed by the wheel furthest from the centre of the turn when turning to the maximum extent. 

How often have the words impasse and turning circle occurred in a corpus of books? (source: Google Ngram Viewer )