1. (

• quoin ,
• coign ,
• coigne ,

) expandable metal or wooden wedge used by printers to lock up a form within a chase ;

2. (

• quoin ,
• coign ,
• coigne ,

) the keystone of an arch ;

3. (

• corner ,
• quoin

) (architecture) solid exterior angle of a building; especially one formed by a cornerstone ;