quoin

It will be observed that portions of a brick have to be inserted near a vertical end or a quoin, in order to start the regular bond.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various

"Knock away the quoin, entirely;" he said to the captain of the gun, when he had got the range; "now mind her when she lifts, forward; keep the ship steady, Sir—fire!"

From The Water-Witch or, the Skimmer of the Seas by James Fenimore Cooper

My knees No che quoin noh Ni gui tick.

From Voyages from Montreal Through the Continent of North America to the Frozen and Pacific Oceans in 1789 and 1793 Vol. I by Alexander Mackenzie

Mount Trafalgar made its first appearance in the form of a huge quoin or wedge, resting longitudinally upon the horizon, with its point towards the south-east.

From Discoveries in Australia, Volume 1. With an Account of the Coasts and Rivers Explored and Surveyed During The Voyage of H.M.S. Beagle, in the Years 1837-38-39-40-41-42-43. By Command of the Lords Commissioners of the Admiralty. Also a Narrative Of Captain Owen Stanley's Visits to the Islands in the Arafura Sea. by John Lort Stokes

The level mark on the quoin is to correspond with the end of the bed.

From Ordnance Instructions for the United States Navy. 1866. Fourth edition. by United States. Navy Dept. Bureau of Ordnance