唇膏 (chúngāo) literally means 'lip ointment' — 唇 (chún) means 'lip', and 膏 (gāo) means 'ointment', 'paste', or 'balm'. Though historically it referred to medicinal lip balms, today it almost exclusively means 'lipstick': a cosmetic product applied to the lips for color, shine, or moisture. It’s a common, everyday term used in beauty contexts, stores, advertisements, and casual conversation.

The word is neutral in register — appropriate for both spoken and written Chinese — and carries no strong stylistic connotation (unlike more poetic or literary alternatives). While younger speakers sometimes use loanwords like 口红 (kǒuhóng, literally 'mouth red') interchangeably, 唇膏 emphasizes texture and function (a smooth, waxy paste), making it especially common when discussing formulation, hydration, or long-wear properties.