免费 (miǎn fèi) literally combines 免 (miǎn), meaning 'to avoid' or 'to exempt', and 费 (fèi), meaning 'fee' or 'cost'. Together, they mean 'free of charge' — indicating that no payment is required for a good or service. It functions primarily as an adjective in Chinese, modifying nouns like 服务 (service), 课程 (course), or 升级 (upgrade).

This term is widely used in everyday contexts: advertisements ('免费试用' — free trial), public services ('免费WiFi'), and digital platforms ('免费下载' — free download). While it can occasionally appear adverbially (e.g., 免费提供), its core grammatical role remains adjectival. Unlike the English word 'free', which can imply liberty (as in 'free speech'), 免费 refers exclusively to absence of monetary cost — never to freedom or autonomy.