The Chinese word 外甥 (wàisheng), meaning "sister's son" or "nephew (from a female perspective)", is formed through semantic compounding. It combines the character 外 (wài), meaning "outside" or "external", with 甥 (shēng), which specifically means "sister's son". The 外 here denotes the kinship line as being "outside" the immediate paternal clan, reflecting the traditional patrilineal family structure where children of one's sister marry into another family and are thus considered part of an "external" lineage. Therefore, the term precisely identifies the nephew as the son of one's sister, distinguishing him from a brother's son, who is called 侄子 (zhízi).