Where does “pen” come from?

pen (Middle Cornish) comes from Old Cornish pen, from Proto-Brythonic penn, from Proto-Celtic kʷennom — head.

Ancestry of “pen”, step by step

StepLanguageWordMeaning
1Old Cornishpenhead
2Proto-Brythonicpennhead
3Proto-Celtickʷennomhead

Words derived from “pen”

Every word from Proto-Celtic kʷennom →Every word from Proto-Brythonic penn →Every word from Old Cornish pen →