WordWeb Online

1. Not having or showing or requiring special skill or proficiency
   "unskilled in the art of rhetoric"; "unskilled labour"; "workers in unskilled occupations are finding fewer and fewer job opportunities"; "unskilled workmanship"
    
2. Lacking professional skill or expertise
   "an unskilled painting"
   - amateurish, amateur, inexpert
    
3. Not doing a good job
   - incompetent

See also: artless, bad, botched, botchy, bungled, bungling, butcherly, clumsy, crude, fumbling, hopeless, humble, incompetent, inexperienced, inexperient [non-standard], lowly, lubberly, menial, out of practice, rough, rusty, semiskilled, unprofessional, unskilful [Brit, Cdn], unskillful [N. Amer], weak

Antonym: skilled