1. Not fair; marked by injustice or partiality or deception
   - unfair 
2. Violating principles of justice
   "unjust punishment"; "an unjust judge"; "an unjust accusation" 
3. Not equitable or fair
   - inequitable

See also: actionable, below the belt, cheating, dirty, dishonorable [US], dishonourable [Brit, Cdn], equity, fairness, foul, partial, raw, unjustly, unjustness, unrighteous, unsporting, unsportsmanlike, wrong, wrongful

Antonym: just

• proscenium
• proscenium arch
• proscenium wall
• prosciutto
• proscribe
• proscribed
• proscription
• proscriptive
• prose
• prose poem
• prosector
• prosecutable
• prosecute
• prosecuting attorney
• prosecuting officer
• prosecution
• prosecutor
• proselyte
• proselytise
• proselytiser
• proselytism
• proselytize
• proselytizer
• prosencephalon
• Proserpina