Definitions

1. noun

A projecting corner of a building, especially one formed by the meeting of two walls.

“The ornate coign of the old mansion was a striking feature of its design.”

2. noun

A projecting corner or angle.

“The sharp coign of the rock made it difficult to climb.”

3. verb

To form or have a coign or projecting corner.

“The new building will coign the corner lot with its design.”