a band that passes underneath a horse or other animal to hold a saddle in place, especially one having a buckle at each end for fastening to straps running from under the flaps of the saddle. See illus. under saddle.
c.1300, "belt around a horse's body," from O.N. gjorð "girdle, belt, hoop," from P.Gmc. *gertu- (cf Goth. gairda "girdle"), from the same source as gird (q.v.). Sense of "measurement around an object" first recorded 1644.