coigne

Noun

coign (plural coigns)

1. A projecting corner or angle; a cornerstone.
   • By many a dern and painful perch
     Of Pericles the careful search
     By the four opposing coigns
     Which the world together joins,
     Is made with all due diligencec. 1607–1608 (date written), William Shakespeare, [George Wilkins?], The Late, and Much Admired Play, Called Pericles, Prince of Tyre. […], London: […] [William White and Thomas Creede] for Henry...
2. The keystone of an arch.
3. A wedge used in typesetting.
4. A a corner of a crystal formed by the intersection of three or more faces at a point (in crystallography)
   • In both the orthogonal and clinographic projections the light rays joining the eye and crystal coigns (solid angles, corners at which three or more edges meet) are all parallel1922, Alfred Tutton, Crystallography and Practical Measurement
5. An original angular elevation of land around which continental growth has taken place (in geology)
   • South of the North American coign we have again a pair of east - west mountain chains1901, The American Geologist: A Monthly Journal of Geology and Allied Sciences

See all 6 meanings of coign