duad vs rack

duad

noun
  • Dwadasama. 

  • A pair or couple. 

  • An unordered pair. 

rack

noun
  • A distaff. 

  • A cranequin, a mechanism including a rack, pinion and pawl, providing both mechanical advantage and a ratchet, used to bend and cock a crossbow. 

  • Any of various kinds of frame for holding luggage or other objects on a vehicle or vessel. 

  • A series of one or more shelves, stacked one above the other 

  • A cut of meat involving several adjacent ribs. 

  • A woman's breasts. 

  • A climber's set of equipment for setting up protection and belays, consisting of runners, slings, carabiners, nuts, Friends, etc. 

  • A friction device for abseiling, consisting of a frame with five or more metal bars, around which the rope is threaded. 

  • A thousand pounds (£1,000), especially if proceeds of crime 

  • Thin, flying, broken clouds, or any portion of floating vapour in the sky. 

  • A bunk. 

  • A grate on which bacon is laid. 

  • A set of antlers (as on deer, moose or elk). 

  • Sleep. 

  • A device, incorporating a ratchet, used to torture victims by stretching them beyond their natural limits. 

  • A piece or frame of wood, having several sheaves, through which the running rigging passes. 

  • A hollow triangle used for aligning the balls at the start of a game. 

  • A bar with teeth on its face or edge, to work with a pawl as a ratchet allowing movement in one direction only, used for example in a handbrake or crossbow. 

  • A set with a distributive binary operation whose result is unique. 

  • A fast amble. 

  • A bar with teeth on its face or edge, to work with those of a gearwheel, pinion, or worm, which is to drive or be driven by it. 

verb
  • To stretch or strain; to harass, or oppress by extortion. 

  • To put the balls into the triangular rack and set them in place on the table. 

  • To (manually) load (a round of ammunition) from the magazine or belt into firing position in an automatic or semiautomatic firearm. 

  • To clarify, and thereby deter further fermentation of, beer, wine or cider by draining or siphoning it from the dregs. 

  • To cause (someone) to suffer pain. 

  • To move the slide bar on a shotgun in order to chamber the next round. 

  • To fly, as vapour or broken clouds. 

  • To amble fast, causing a rocking or swaying motion of the body; to pace. 

  • To drive; move; go forward rapidly; stir. 

  • To place in or hang on a rack. 

  • To torture (someone) on the rack. 

  • To tend to shear a structure (that is, force it to bend, lean, or move in different directions at different points). 

  • To strike in the testicles. 

  • To bind together, as two ropes, with cross turns of yarn, marline, etc. 

  • To wash (metals, ore, etc.) on a rack. 

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