‘表姥姥’ is a kinship term referring specifically to one’s mother’s cousin’s mother — that is, the mother of one’s maternal aunt or uncle who is related by marriage or distant blood (not direct lineage). The character ‘表’ (biǎo) indicates a ‘collateral’ or ‘affinal’ relationship — typically used for relatives on the mother’s side or those connected through marriage, distinguishing them from ‘亲’ (qīn) ‘direct’ relatives. ‘姥姥’ (lǎo lǎo) means ‘maternal grandmother’, so ‘表姥姥’ literally combines ‘collateral’ + ‘maternal grandmother’, signaling she is not the speaker’s actual maternal grandmother but a parallel elder in the extended maternal line.

This term reflects the precision and hierarchy embedded in Chinese kinship terminology. It is rarely used in casual daily speech today, especially among younger generations, and often appears in formal family trees, genealogical discussions, or when clarifying complex extended-family connections. While grammatically correct, many native speakers would instead describe the relationship circumstantially (e.g., ‘我妈表姐的妈妈’) rather than use ‘表姥姥’ directly.