留言 (liú yán) literally combines 留 (liú), meaning 'to leave' or 'to remain', and 言 (yán), meaning 'words' or 'speech'. Together, they form a compound meaning 'to leave a message' — typically in writing or digitally, such as on a website, social media platform, answering machine, or guestbook. It emphasizes the act of recording a brief communication for someone who is not present.

This word functions both as a verb ('I left a message') and a noun ('I checked my messages'). It’s commonly used in everyday digital and interpersonal contexts — for example, when contacting customer service, responding to a post, or sending feedback. Unlike 口信 (kǒu xìn, an oral message passed by person), 留言 implies written or recorded form and often carries a sense of informality and convenience.