Source : Webster's Revised Unabridged Dictionary (1913)

Proparoxytone \Pro`par*ox"y*tone\, n. [Gr. ?. See {Pro-}, and
   {Paroxytone}.] (Gr. Gram.)
   A word which has the acute accent on the antepenult.

Source : WordNet®

proparoxytone
     n : word having stress or acute accent on the antepenult