The Collaborative International Dictionary of English v.0.48:
Gunpowder \Gun"pow`der\ (g[u^]n"pou`d[~e]r), n. (Chem.)
A black, granular, explosive substance, consisting of an
intimate mechanical mixture of saltpeter, charcoal, and
sulphur. It is used in gunnery and blasting.
Note: Gunpowder consists of from 70 to 80 per cent of
potassium nitraate (niter, saltpeter), with 10 to 15
per cent of each of the other ingredients. Its
explosive energy is due to the fact that it contains
the necessary amount of oxygen for its own combustion,
and liberates gases (chiefly nitrogen and carbon
dioxide), which occupy a thousand or fifteen hundred
times more space than the powder which generated them.
Gunpowder pile driver, a pile driver, the hammer of which
is thrown up by the explosion of gunpowder.
Gunpowder plot (Eng. Hist.), a plot to destroy the King,
Lords, and Commons, in revenge for the penal laws against
Catholics. As Guy Fawkes, the agent of the conspirators,
was about to fire the mine, which was placed under the
House of Lords, he was seized, Nov. 5, 1605. Hence, Nov. 5
is known in England as
Guy Fawkes Day.
Gunpowder tea, a species of fine green tea, each leaf of
which is rolled into a small ball or pellet.