WordWeb Online

1. Difficult to use or handle or manage because of size or weight or shape
   "we set about towing the unwieldy structure into the shelter"; "almost dropped the unwieldy parcel"
   - unmanageable
    
2. Difficult to work or manipulate
   "unwieldy rules and regulations"
    
3. Lacking grace in movement or posture
   "heaved his unwieldy figure out of his chair"
   - gawky, clumsy, clunky, ungainly, klutzy [N. Amer]

See also: awkward, bunglesome, clumsy, cumbersome, cumbrous, impractical, ungainly, unwieldiness

Antonym: wieldy