English 'nephew' comes from Old French 'neveu,' from Latin 'nepōs' meaning 'grandson or nephew,' from PIE *népōts — the same root that, via Italian 'nipote,' gave English 'nepotism,' permanently linking the word for a sibling's son with the history of papal favouritism.
The son of one's brother or sister.
From Old French 'neveu,' from Latin 'nepōtem' (accusative of 'nepōs'), meaning 'grandson' or 'nephew' — and sometimes, in later Latin, 'descendant' more broadly. The Latin 'nepōs' descends from PIE *népōts meaning 'grandson' or 'nephew,' a masculine form related to *neptíh₂ (the feminine, ancestor of 'niece'). The same PIE root produced the notorious word 'nepotism,' coined in the 17th century from Italian 'nipote' (nephew), originally referring to the practice of popes appointing their 'nephews' — often a euphemism for illegitimate
The word 'nepotism' — favouritism shown to relatives — derives directly from Italian 'nipote' (nephew), coined to describe the habit of Renaissance popes appointing their nephews to lucrative Church offices, the word itself being a monument to one of the Church's most persistent scandals.