Source : Webster's Revised Unabridged Dictionary (1913)

Teasel \Tea"sel\, n. [OE. tesel, AS. t?sel, t?sl, the fuller's
   herb. See {Tease}.] [Written also {tassel}, {tazel},
   {teasle}, {teazel}, and {teazle}.]
   1. (Bot.) A plant of the genus {Dipsacus}, of which one
      species ({D. fullonum}) bears a large flower head covered
      with stiff, prickly, hooked bracts. This flower head, when
      dried, is used for raising a nap on woolen cloth.

   Note: Small teasel is {Dipsacus pilosus}, wild teasel is {D.
         sylvestris}.

   2. A bur of this plant.

   3. Any contrivance intended as a substitute for teasels in
      dressing cloth.

   {Teasel frame}, a frame or set of iron bars in which teasel
      heads are fixed for raising the nap on woolen cloth.