Regen \r(e)-gen\ as a boy's name is a variant of Regan (Gaelic). See for meaning of Regen.

The baby name Regen sounds like Reagen and Regin. Other similar baby names are Beagen, Bergen, Dagen, Eagen, Eugen, Hagen, Keegen, Keagen, Kagen, Logen, Rien, Raven, Reagan, Rene, Regino, Regis, Ren, Reuben, Ruben, Reuven, Rigel, Rogan, Roger, Rowen, Rozen, Ryen, Ryden and Teigen.