Galen \g(a)-len\ as a boy's name (also used as girl's name Galen), is pronounced GAY-len. It is of Greek origin, and the meaning of Galen is "calm". From Galenus, which derives from "galene". The name of a second-century Greek physician whose research provided a basis for accepted medical practices for 1500 years.
Galen has 15 variant forms: Gaelan, Gaillen, Galan, Galeno, Galin, Galyn, Gaylen, Gaylin, Gaylinn, Gaylon, Jalen, Jalin, Jalon, Jaylen and Jaylon.