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a(d)- Prefix "at," "towards"
From Latin ad-. From Proto-Italic *ad- 'id.,' a grammaticalized prefix from the preposition *ad (see a).
Indo-European
Romance
Asturian a-, Portuguese a-, Galician a-, Catalan a-, French a-, Italian a-, Romanian a-
Italic
South Picene ad-, Oscan ad-, ar-, Volscian ar-, Umbrian ař-, -ař
Celtic
Gaulish ad-, Old Irish ad-, Welsh ad-
Germanic
Old High German az-
Phrygian
Phrygian αδ- (ad)