1. not prepared according to Jewish dietary laws
Usage: religious
2. improper, unethical, or questionable
Usage: informal

Examples

• The restaurant served unkosher meat that mixed dairy and beef.
• Eating pork is considered unkosher in Jewish dietary law.
• His business dealings seemed unkosher to the investigators.
• The whole arrangement struck me as unkosher.
• She refused to eat at the unkosher deli.
• That politician’s campaign financing looks unkosher.