孙女 (sūnnǚ) is a compound noun meaning 'granddaughter' — the daughter of one's son or daughter. The first character, 孙 (sūn), means 'grandchild' and historically emphasized paternal-line descendants, while 女 (nǚ) means 'female' or 'daughter'. Together, they specify a female grandchild. This term is used in family contexts, formal documents, introductions, and everyday conversation when referring to or addressing a granddaughter.

Unlike English, which uses the same word 'granddaughter' regardless of lineage, Chinese distinguishes between paternal and maternal grandchildren only in very formal or traditional settings; 孙女 covers both unless specified further (e.g., 外孙女 for maternal granddaughter). It’s a respectful, neutral term — never diminutive or informal — and commonly appears with possessive pronouns (e.g., 我的孙女) or kinship titles (e.g., 小孙女 for 'little granddaughter').