From Proto-Italic *nowos, from Proto-Indo-European *néwos. Cognates include Old English nīewe (English new), Ancient Greek νέος (néos), Proto-Slavic *novъ, and Sanskrit नव (náva).
Proto-Italic *nowos fails to become Latin *nuus due to specific conditions in the development of Latin, namely -o-(w)- being in the first syllable, whereas *dē nowōd (“anew”) became dēnuō.