The Proto-Indo-European word *ad-
Word *ad-
Meaning to, by, at
See also Phrygian: ΑΔ- ‘to, by, at’
Cappadocian Greek: αδέ ‘here, over here’
Pontian: αδακά ‘here, over here’
Proto-Italic: *ad ‘to’
Synonyms *h₁epi~h₁opi, *do~de, *hₐed

Other words that might be of interest
*pro ‘away, forward, ahead’