Where does “quatre” come from?
quatre (Middle French) comes from Old French quatre, from Latin quattŭor, from Portuguese quarto, from Old Portuguese quarto, from Latin quārtus, from Proto-Indo-European kʷeturtos, from Proto-Indo-European kʷetwóres, from Proto-Indo-European kʷe- — and.
quatre (Middle French): four
Ancestry of “quatre”, step by step