2. (Mining) A door in a level for regulating the ventilating
current; -- called also {weather door}. --Raymond.
{Trapdoor spider} (Zo["o]l.), any one of several species of
large spiders which make a nest consisting of a vertical
hole in the earth, lined with a hinged lid, like a
trapdoor. Most of the species belong to the genus
{Cteniza}, as the California species ({C. Californica}).