1. [n]  the basic unit of money in North Korea
2. [n]  the basic unit of money in South Korea
3. [adj]  not subject to defeat; "with that move it's a won game"

WON is a 3 letter word that starts with W.

1. \Won\,
   imp. & p. p. of {Win}.
   
   

2. \Won\, v. i. [See 1st {Wone}.]
   To dwell or abide. [Obs. or Scot.] `` Where he wans in forest
   wild.'' --Milton.
   
         This land where I have woned thus long.  --Spenser.
   
   

3. \Won\, n.
   Dwelling; wone. [Obs.] --Spenser.