Deh₂nu
Deh₂nu-  is a Proto-Indo-European goddess of rivers. Some people think that this is based on the Vedic goddess Dānu, the Irish goddess Danu, the Welsh goddess Don, and the names of some rivers such as the Danube, Don, Dnieper, and Dniester. But, Mallory and Adams say that there is no proof for a specific river goddess in this mythology, only the idea of rivers being important in Indic tradition.