Trap-door

She then went to look into the mouse-trap, where she found six mice, all alive. She ordered Cinderella to lift the trap-door, when, giving each mouse, as it went out, a little tap with her wand, it was that moment turned into a fine horse, and the six mice made a fine set of six horses of a beautiful mouse-colored, dapple gray.

Your garret-windows therefore ſhould always be ſecured, and trap-doors opening to the leads well bolted.

A bell tinkles, and forthwith the trap-doors beneath the stage open and a variety of musical instruments, followed by an equally diversified assortment of heads, are thrust through.

It was reached by a trap-door in the middle of the floor, from which a ladder led down into the small, dark hole.

Then I went to the roof. […] A ladder and a trap-door led to it, and it required some nice balancing on my part to get up with my useless arm. […] The roof of the empty house adjoined mine along the back wing, but investigation showed that the trap-door across the low dividing wall was bolted underneath.

Oozing and surging up out of that yawning trap-door in the Cyclopean crypt I had glimpsed such an unbelievable behemothic monstrosity that I could not doubt the power of its original to kill with its mere sight.