Quoin

koin, n. ( arch it. ) a wedge used to support and steady a stone: an external angle, esp. of a building: ( gun. ) a wedge of wood or iron put under the breech of heavy guns or the muzzle of siege-mortars to raise them to the proper level: ( print. ) a wedge used to fasten the types in the forms.— v.t. to wedge or steady with quoins. [ Coin. ]