In timber framing, a subsidiary (usually vertical) member (or scantling) in a wall or partition. In close-studding the spaces between studs are about the same in width as the studs themselves, a profligate use of material intended for show rather than for any practical purpose. Herringbone-studding is set at an angle (usually 45°) to the posts, filling the space framed by the posts and rails. A cruck-stud is set on and fixed to the outside of a cruck blade.
Alcock, Barley, Dixon, & Meeson (1996)