piedroit
/ˈpjɛdrwɑ/Architecture. Now rare
noun
A square pier or pillar attached to a wall, similar to a pilaster but having neither a base nor a capital.
Origin
Late 17th century; earliest use found in Edward Phillips (b. 1630), writer and biographer. From French pied droit, piédroit upright post of a door or window frame, square pier, vertical wall supporting a vault from pied foot + droit straight.