‘鼠辈’ literally means 'rat generation' or 'rat kind'—a compound formed by 鼠 (shǔ, 'rat') and 辈 (bèi, a suffix meaning 'generation', 'kind', or 'group of people'). Though it contains an animal character, it is never used to refer to actual rats; instead, it functions as a highly derogatory noun for contemptible, despicable, or despicable people—often implying cowardice, treachery, or low moral standing. The term carries strong negative connotations and is typically used in heated rhetoric, historical narratives, or literary criticism.

It’s commonly found in classical or semi-formal registers—especially in historical dramas, martial arts novels, or political polemics—and rarely appears in polite conversation. Unlike neutral terms like 人们 (rénmen, 'people'), 鼠辈 always signals disdain and moral condemnation. Its tone is archaic yet still understood today, evoking imagery of vermin to underscore worthlessness or deceitfulness.