Illustrated Architecture Dictionary
A door that slides into and out of a recess in a doorway wall.
Though pocket doors were common as early as the 1850s, most of them used V-rollers (sheaves) that were in the bottom of the door and ran on a track on the floor—a system that grew noisy or difficult to operate if the floor sagged.
Shifting the track and moving hardware to the top of the door circumvented this problem, and by the 1880s there were several patented top-hung hardware systems on the market.
- Gordon Bock, Old House Online (Sept. 2012)
Examples from Buffalo architecture: