(1):

(n.) The measure round the body, as at the waist or belly; the circumference of anything.

(2):

(n.) A band or strap which encircles the body; especially, one by which a saddle is fastened upon the back of a horse.

(3):

(n.) A small horizontal brace or girder.

(4):

(v. t.) To bind as with a girth.