Source : Webster's Revised Unabridged Dictionary (1913)

Prowess \Prow"ess\, n. [OF. proece, proesce, F. prouesse. See
   {Prow}, a.]
   Distinguished bravery; valor; especially, military bravery
   and skill; gallantry; intrepidity; fearlessness. --Chaucer.
   Sir P. Sidney.

         He by his prowess conquered all France.  --Shak.

Source : WordNet®

prowess
     n : a superior skill that you can learn by study and practice
         and observation; "the art of conversation"; "it's quite
         an art" [syn: {art}, {artistry}]