idleness vs slowness

idleness

noun
  • The state of being idle; inactivity. 

  • Groundlessness; worthlessness; triviality; vanity; frivolity. 

  • The state of being indolent; indolence. 

slowness

noun
  • The quality or state of being slow. 

  • A unit, the reciprocal of velocity, that delineates the amount of time required for an object to travel a given distance. 

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