stagger vs tread

stagger

verb
  • In standing or walking, to sway from one side to the other as if about to fall; to stand or walk unsteadily; to reel or totter. 

  • To cease to stand firm; to begin to give way; to fail. 

  • To begin to doubt and waver in purposes; to become less confident or determined; to hesitate. 

  • To arrange (a series of parts) on each side of a median line alternately, as the spokes of a wheel or the rivets of a boiler seam. 

  • To cause to doubt and waver; to make to hesitate; to make less steady or confident; to shock. 

  • To arrange similar objects such that each is ahead or above and to one side of the next. 

  • To schedule in intervals or at different times. 

  • To cause to reel or totter. 

noun
  • An unsteady movement of the body in walking or standing as if one were about to fall; a reeling motion. 

  • The spacing out of various actions over time. 

  • One who attends a stag night. 

  • The horizontal positioning of a biplane, triplane, or multiplane's wings in relation to one another. 

  • Bewilderment; perplexity. 

  • The difference in circumference between the left and right tires on a racing vehicle. It is used on oval tracks to make the car turn better in the corners. 

  • A disease of horses and other animals, attended by reeling, unsteady gait or sudden falling. 

tread

verb
  • To step or walk (on or across something); to trample. 

  • To proceed, to behave (in a certain manner). 

  • To beat or press with the feet. 

  • To work a lever, treadle, etc., with the foot or the feet. 

  • To crush grapes with one's feet to make wine 

  • To step or walk upon. 

  • To copulate; said of (especially male) birds. 

  • To go through or accomplish by walking, dancing, etc. 

  • To copulate with. 

  • To crush under the foot; to trample in contempt or hatred; to subdue. 

noun
  • A step taken with the foot. 

  • The grooves carved into the face of a tire, used to give the tire traction. 

  • The chalaza of a bird's egg; the treadle. 

  • The grooves on the bottom of a shoe or other footwear, used to give grip or traction. 

  • A bruise or abrasion produced on the foot or ankle of a horse that interferes, or strikes its feet together. 

  • The horizontal part of a step in a flight of stairs. 

  • The top of the banquette, on which soldiers stand to fire over the parapet. 

  • The act of avian copulation in which the male bird mounts the female by standing on her back. 

  • A manner of stepping. 

  • The sound made when someone or something is walking. 

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