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a (Adverb) "at," "in"
A post-Latin development from the 12th cent., deriving from Latin ad "to," "toward." From Proto-Italic *ad 'id.' From Proto-Indo-European *h2ed 'id.'
Indo-European
Romance
Asturian a, Portuguese a, Galician a, Catalan a, French à, Italian a, ad, Romanian a
Italic
Oscan az "by" (< *ad-s)
Celtic
Welsh â
Germanic
Gothic at, Old Icelandic at, Old English æt (English at)