A hole made by a mouse, for passage or abode, as in a wall; hence, a very small hole like that gnawed by a mouse.
n: shallow bores under the rig floor, usually lined with pipe, in which joints of drill pipe are temporarily suspended for later connection to the drill string.
an opening that is made to the interior or exterior of a structure (walls, floors, ceilings, roofs) to facilitate inter- and intra-building communications and movement
a shallow bore hole under the rig floor, usually lined with pipe, in which joints of drill pipe are temporarily placed
The mousehole is the storage area on a drilling rig where the next joint of drilling pipe is held until needed. This hole is in the floor of the rig, bored into the earth for a short ways, and usually lined with a metal casing.