叔父 (shū fù) is a formal, respectful term for one’s paternal uncle — specifically, the younger brother of one’s father. The character 叔 (shū) means 'younger uncle' and historically denotes relative age among male siblings, while 父 (fù) means 'father', signaling the familial generation and patriarchal connection. Together, they form a compound noun that emphasizes both kinship rank and generational position within traditional Chinese family structure.

This term is commonly used in written Chinese, formal speech, official documents, or when addressing or referring to the uncle with deference — especially in contexts like family introductions, ancestral records, or ceremonies. It is less common in casual daily conversation among younger generations, who may prefer simpler terms like 叔叔 (shū shu). Unlike maternal uncles (who are called 舅父 jiù fù), 叔父 strictly refers only to the father’s side of the family, reflecting China’s patrilineal naming conventions.