A metal flap installed at the bottom of the
bowl of a chemical or
pit toilet, which blocks out unwanted odors. The flap is hinged and sprung in such a way as to only open when a certain amount of weight is applied to it.
A common accessory for this device is the stoker - a small
stick which is used to manually operate the flap, should it for some reason fail to open.
"I say, Thomas, would you be so kind as to pass over a stoker, I have produced a rather large
stool which has become lodged in the
shit flap".