WordWeb Online

1. Lacking in value or merit
   "dispel a student whose conduct is deemed unworthy"; "unworthy of forgiveness"
    
2. Not deserving
   "the unworthy poor"
   - undeserving
    
3. Morally reprehensible
   "would do something as unworthy as murder"
   - despicable, ugly, vile, slimy, worthless, wretched

Derived forms: unworthier, unworthiest

See also: contemptible, dishonorable [US], dishonourable [Brit, Cdn], evil, unmerited, unmeritorious, unrighteous, unworthily, unworthiness, worthiness, worthless

Antonym: worthy