coign

[koin] /kɔɪn/
noun, verb (used with object)
1.
quoin.
British Dictionary definitions for coign

coign

/kɔɪn/
noun
1.
variant spellings of quoin

quoin

/kwɔɪn; kɔɪn/
noun
1.
an external corner of a wall
2.
Also called cornerstone. a stone forming the external corner of a wall
3.
another name for keystone (sense 1)
4.
(printing) a metal or wooden wedge or an expanding mechanical device used to lock type up in a chase
5.
a wedge used for any of various other purposes, such as (formerly) to adjust elevation in muzzle-loading cannon
Word Origin
C16: variant of coin (corner)
Word Origin and History for coign
n.

archaic spelling of quoin (q.v.), surviving only in Shakespeare's coign of vantage ("Macbeth" I.vi.), popularized by Sir Walter Scott, properly "a projecting corner" (for observation).