drop-door

Any structural weakness caused by severing the two lowest boards is counteracted by the two grooved pieces in which the drop-door moves.

Things To Make Archibald Williams

But quick as were the motions of Black Bruin, the trap was quicker, for the moment the trigger was loosed, the cord let go the drop-door and down it came with a great bang.

Black Bruin The Biography of a Bear Clarence Hawkes 1901

There was a drop-door over the opening, held up by a hasp.

The Skipper and the Skipped Being the Shore Log of Cap'n Aaron Sproul Holman Day 1900

President Kitchen let loose the hasp that held up the drop-door and fairly "pegged" Mr. Todd out of sight.

The Skipper and the Skipped Being the Shore Log of Cap'n Aaron Sproul Holman Day 1900

The walls of the cage was made of thick spars of wood, with interstices between them, through which the lion could both see and be seen: probably the top was entirely covered with boards, and upon these was raised a sort of low hut or sentry-box, just large enough to contain a man, who, when the proper moment arrived, peeped forth from his concealment and cautiously raised the front of the trap, which was a kind of drop-door working in a groove.

The Seven Great Monarchies Of The Ancient Eastern World, Vol 2. (of 7): Assyria The History, Geography, And Antiquities Of Chaldaea, Assyria, Babylon, Media, Persia, Parthia, And Sassanian or New Persian Empire; With Maps and Illustrations. George Rawlinson 1857