tail-bay

Century Dictionary and Cyclopedia

1. n. In a canal-lock, the space between the tail-gates and the lower pond.
2. n. In a framed floor, one of the spaces between a girder and the wall.

Wiktionary

1. n. architecture One of the joists which rest one end on the wall and the other on a girder.
2. n. architecture The space between a wall and the nearest girder of a floor.
3. n. The part of a canal lock below the lower gates.

GNU Webster's 1913

1. n. (Arch.) One of the joists which rest one end on the wall and the other on a girder; also, the space between a wall and the nearest girder of a floor. Cf. case-bay.
2. n. The part of a canal lock below the lower gates.