illegal

Not allowed by the law.

• These drugs are illegal.
• It is illegal to drive without a license.
• Police stopped the illegal trade in rare birds.

How to use it: illegal to do something (It is illegal to sell these animals.)

Similar words: unlawful, illicit

Opposites: legal, lawful

Common phrases: illegal activity, illegal drugs, illegal trade, illegal sale

Not allowed by the rules of a game, sport, or system.

• That is an illegal move in chess.
• The referee punished an illegal tackle.
• The program rejected an illegal command.

Similar words: forbidden, disallowed

Opposites: legal, permitted

Common phrases: illegal move, illegal tackle, illegal position