The Collaborative International Dictionary
Bull \Bull\, a. Of or pertaining to a bull; resembling a bull; male; large; fierce.
Bull bat (Zo["o]l.), the night hawk; -- so called from the loud noise it makes while feeding on the wing, in the evening.
Bull calf. (a) A stupid fellow.
Bull mackerel (Zo["o]l.), the chub mackerel.
Bull pump (Mining), a direct single-acting pumping engine, in which the steam cylinder is placed above the pump.
Bull snake (Zo["o]l.), the pine snake of the United States.
Bull stag, a castrated bull. See Stag.
Bull wheel, a wheel, or drum, on which a rope is wound for lifting heavy articles, as logs, the tools in well boring, etc.
Wiktionary
n. (context mining English) A direct single-acting pumping engine, in which the steam cylinder is placed above the pump.