The Collaborative International Dictionary of English v.0.48:

Unsharpened \Unsharpened\
   See sharpened.

WordNet (r) 3.0 (2006):

unsharpened
    adj 1: not sharpened

Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "unsharpened":
   abrupt, bluff, blunt, blunt-edged, blunt-ended, blunt-pointed,
   blunted, bluntish, dull, dull-edged, dull-pointed, dulled, dullish,
   edgeless, faired, obtuse, pointless, rounded, smoothed, unedged,
   unpointed, unsharp