To bend or curve

To guide and manage, or restrain, as with a curb; to bend
to one’s will; to subject; to subdue; to restrain; to confine; to keep
in check.

To furnish wich a curb, as a well; also, to restrain by a
curb, as a bank of earth.

To bend; to crouch; to cringe.

That which curbs, restrains, or subdues; a check or
hindrance; esp., a chain or strap attached to the upper part of the
branches of a bit, and capable of being drawn tightly against the lower
jaw of the horse.

A frame or wall round the mouth of a well; also, a frame
within a well to prevent the earth caving in.

A curbstone.

A swelling on the back part of the hind leg of a horse, just
behind the lowest part of the hock joint, generally causing lameness.