Tread v. i. [imp. Trod p. p. Trodden Trod; p. pr. & vb. n. Treading.]
  1. To set the foot; to step.
     Where'er you tread, the blushing flowers shall rise.   --Pope.
     Fools rush in where angels fear to tread.   --Pope.
  The hard stone
  Under our feet, on which we tread and go.   --Chaucer.
  2. To walk or go; especially, to walk with a stately or a cautious step.
     Ye that . . . stately tread, or lowly creep.   --Milton.
  3. To copulate; said of birds, esp. the males.
  To tread on or To tread upon. (a) To trample; to set the foot on in contempt. “Thou shalt tread upon their high places.” --Deut. xxxiii. 29. (b) to follow closely. “Year treads on year.” --Wordsworth.
  To tread upon the heels of, to follow close upon. “Dreadful consequences that tread upon the heels of those allowances to sin.” --Milton.
     One woe doth tread upon another's heel.   --Shak.