coign

Meanings

1. A projecting corner or angle; a cornerstone.
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)
5. An original angular elevation of land around which continental growth has taken place (in geology)

1. To furnish with coigns.

Etymology

Variant of quoin.