stumble vs toboggan

stumble

verb
  • To trip or fall; to walk clumsily. 

  • To cause to stumble or trip. 

  • To make a mistake or have trouble. 

  • To strike or happen (upon a person or thing) without design; to fall or light by chance; with on, upon, or against. 

  • To mislead; to confound; to cause to err or to fall. 

noun
  • An error or blunder. 

  • A fall, trip or substantial misstep. 

  • A clumsy walk. 

toboggan

verb
  • To go downhill unstoppably until one reaches the bottom. 

  • To slide down a hill on a toboggan or other object. 

  • To fly sharply downward so as to build up speed to facilitate in-flight refueling of a faster aircraft. 

noun
  • A long sled without runners, with the front end curled upwards, which may be pulled across snow by a cord or used to coast down hills. 

  • Something which, once it starts going (figuratively) downhill, is unstoppable until it reaches the bottom. 

  • A knit cap, designed to provide warmth in cold weather. 

  • A similar sled of wood, pulled by dogs, possibly with steel runners, made to transport cargo. 

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