noun, idiom · a person who betrays their country, cause, or group

军队内部出了一个奸，泄露了重要机密。

adjective · cunning, sly, or deceitful in behavior

那人性格极奸，你平时要多留个心眼。

noun · to engage in illicit sexual relations or sexual intercourse outside of marriage

他们二人私通，勾搭成奸，被众人撞见了。

expression · evil, malicious, or treacherous in character

他是个大奸大恶之人。

verb · to violate someone sexually or commit a sexual assault

这种行奸的恶徒必须受到法律严惩。