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en (Preposition) "in," "at," "about," "against," "within," "into"

10th cent. From Latin in 'id.' (Archaic Latin en). From Proto-Italic *en 'id.' From Proto-Indo-European *h1en 'id.'

Romance: Western Vulgar Latin: Portuguese em, Catalan en, French en, Italian in; Eastern Vulgar Latin: Aromanian ãn, Romanian în

Italic: Oscan en, Paelignian i

Indo-European: Celtic: Old Irish i, Old Welsh in, Old Breton en, Cornish yn; Germanic: Gothic in, Old Norse í, Old Saxon in, Old High German in, Old English in (English in); Balto-Slavic: Old Church Slavonic vъn, Russian vo, Lithuanian į, Old Prussian en; Hellenic: Ancient Greek ἐν (en); Armenian: i; Tocharian: A yn-, B in-