English 'uncle' comes from Old French 'oncle,' from Latin 'avunculus' meaning 'mother's brother' — a diminutive of 'avus' (grandfather) rooted in PIE *h₂éwh₂os, reflecting an ancient distinction between the maternal and paternal uncle that Latin preserved but English eventually abandoned.
The brother of one's father or mother; also the husband of one's aunt.
From Old French 'oncle,' from Latin 'avunculus' meaning 'mother's brother,' a diminutive of 'avus' meaning 'grandfather.' The Latin word is from PIE *h₂éwh₂os, a root denoting a maternal grandfather or uncle. The Romans distinguished sharply between the paternal uncle ('patruus,' from 'pater') and the maternal uncle ('avunculus'), reflecting an ancient Indo-European kinship system in which the mother's brother held a distinct and often privileged social role. English collapsed this distinction after the Norman