Klein \k-lein\ as a boy's name is of German origin, and the meaning of Klein is "small".
Klein has 3 variant forms: Kleiner, Kleinert and Kline.
Baby names that sound like Klein are Kleon, Cleon, Glen, Glin, Glenn, Kalin, Kalen, Kaelin, Kellin, Kelwin, Kilean and Kylen.