mid-14c., from O.Fr. gable, from O.N. gafl (in north of England, directly from O.N.), probably from a P.Gmc. root meaning "fork" (cf. O.E. gafol, geafel "fork," M.H.G. gabel "pitchfork"), from PIE *ghebhel (cf. O.Ir. gabul "forked twig"). So called from the Y-shaped timber supports of the roof at gable ends. Related: Gabled; gables.