Blain \b-lain\ as a boy's name is pronounced blayn. It is of Gaelic origin, and the meaning of Blain is "yellow". Anglicized form of the Gaelic personal name Bl?, derived from Gaelic "bl?. May also possibly mean "slender" in Gaelic. Name of an early Celtic saint (sixth century). Magician David Blaine.
Blain has 4 variant forms: Blaine, Blane, Blaney and Blayne.