1. to make something illegal by law; to prohibit or ban something through legislation

Examples

• The government decided to illegalize the sale of certain chemicals.
• Many countries have moved to illegalize smoking in public places.
• The new administration promised to illegalize several harmful substances.
• Environmental groups are pushing to illegalize single-use plastics.
• The city council voted to illegalize parking on that street.
• They want to illegalize the practice due to safety concerns.