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a(d)- Prefix "at," "towards"

From Latin ad-. -d- is eliminated under the influence of some consonants. For example, abogado from Latin advocatus. From Proto-Italic *ad- 'id.' Grammaticalized prefix from the preposition *ad (see a).

Romance: Western Vulgar Latin: Asturian a-, Portuguese a-, Galician a-, Catalan a-, French a-, Italian a-; Eastern Vulgar Latin: Romanian a-

Italic: South Picene ad-, Oscan ad-, ar-, Volscian ar-, Umbrian ař-, -ař

Indo-European: Celtic: Gaulish ad-, Old Irish ad-, Welsh ad-; Phyrgian: αδ- (ad); Germanic: Old High German az-