1. (noun)quoin, coign, coigne expandable metal or wooden wedge used by printers to lock up a form within a chase Synonyms: coign, quoin, coigne, corner
2. (noun)quoin, coign, coigne the keystone of an arch Synonyms: coign, quoin, coigne, corner
3. (noun)corner, quoin (architecture) solid exterior angle of a building; especially one formed by a cornerstone Synonyms: recess, corner, box, street corner, nook, recession, niche, quoin, coigne, turning point, coign