idler vs washboard

idler

noun
  • A mechanical device such as a pulley or wheel that does not transmit power, but supports a moving belt etc. 

  • One who idles; one who spends his or her time in inaction. 

  • One who idles; a lazy person; a sluggard. 

washboard

noun
  • Such a board used as a simple percussion instrument. 

  • A stretch of ripples or bumps on a dirt or gravel road caused by interaction between traffic and road surface. 

  • A board fastened along a ship's gunwale to prevent splashing; a splashboard. 

  • A board with a corrugated surface against which laundry may be rubbed. 

verb
  • To play a washboard. 

  • To move up and down or back and forth across the surface of a hive, possibly to lay down a layer of propolis and wax. 

  • To produce a rippled texture on a surface. 

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