‘同伙’ (tóng huǒ) literally combines ‘同’ (tóng), meaning ‘same’ or ‘together’, and ‘伙’ (huǒ), meaning ‘companion’ or ‘group’. Together, it refers to someone who participates with another person in a shared activity—especially one that is illegal, unethical, or socially disapproved. Unlike neutral terms like ‘partner’ or ‘colleague’, 同伙 carries a distinctly negative connotation and implies joint responsibility for wrongdoing.

The word is commonly used in law enforcement, news reports, and everyday speech when discussing crimes, scams, or misbehavior. It’s rarely used for harmless collaboration—e.g., you wouldn’t call your study group 同伙. Grammatically, it functions as a countable noun and often appears with modifiers like ‘犯罪’ (fàn zuì, ‘criminal’) or ‘可疑’ (kě yí, ‘suspicious’) to reinforce its negative sense. While historically linked to banditry or underground groups, modern usage extends to fraud, cheating, or even minor rule-breaking among peers.