The Collaborative International Dictionary of English v.0.48:

Trice \Trice\, n. [Sp. tris the noise made by the breaking of
   glass, an instant, en un tris in an instant; probably of
   imitative origin.]
   A very short time; an instant; a moment; -- now used only in
   the phrase in a trice. "With a trice." --Turbervile. " On a
   trice." --Shak.
   [1913 Webster]

         A man shall make his fortune in a trice. --Young.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Trice \Trice\, v. t. [OE. trisen; of Scand. or Low German
   origin; cf. Sw. trissa a sheave, pulley, triss a spritsail
   brace, Dan. tridse a pulley, tridse to haul by means of a
   pulley, to trice, LG. trisse a pulley, D. trijsen to hoist.]
   [Written also trise.]
   1. To pull; to haul; to drag; to pull away. [Obs.]
      [1913 Webster]

            Out of his seat I will him trice.     --Chaucer.
      [1913 Webster]

   2. (Naut.) To haul and tie up by means of a rope.
      [1913 Webster]

WordNet (r) 3.0 (2006):

trice
    n 1: a very short time (as the time it takes the eye to blink or
         the heart to beat); "if I had the chance I'd do it in a
         flash" [syn: blink of an eye, flash, heartbeat,
         instant, jiffy, split second, trice, twinkling,
         wink, New York minute]
    v 1: raise with a line; "trice a window shade" [syn: trice,
         trice up]
    2: hoist up or in and lash or secure with a small rope [syn:
       trice, trice up]

Moby Thesaurus II by Grady Ward, 1.0:

27 Moby Thesaurus words for "trice":
   breath, coup, crack, flash, half a jiffy, half a mo, half a second,
   half a shake, instant, jiff, jiffy, microsecond, millisecond,
   minute, moment, sec, second, shake, split second, stroke, tick,
   twink, twinkle, twinkling, twitch, two shakes, wink