circular vs washboard

circular

verb
  • To extend in a circular direction. 

  • To distribute circulars to or at. 

noun
  • Synonym of flyer: a printed advertisement, directive, or notice intended for mass circulation. 

  • A shuttle bus with a circular route. 

adj
  • Referring back to itself, so as to prevent computation or comprehension; infinitely recursive. 

  • Circuitous or roundabout. 

  • Of or relating to a circle. 

  • Distributed to a large number of persons. 

  • In the shape of, or moving in a circle. 

washboard

verb
  • To produce a rippled texture on a surface. 

  • 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. 

noun
  • 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. 

  • Such a board used as a simple percussion instrument. 

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

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