from
The Collaborative International Dictionary of English v.0.48
Smut \Smut\, n. [Akin to Sw. smuts, Dan. smuds, MHG. smuz, G.
schmutz, D. smet a spot or stain, smoddig, smodsig,
smodderig, dirty, smodderen to smut; and probably to E.
smite. See {Smite}, v. t., and cf. {Smitt}, {Smutch}.]
1. Foul matter, like soot or coal dust; also, a spot or soil
made by such matter.
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2. (Mining) Bad, soft coal, containing much earthy matter,
found in the immediate locality of faults.
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3. (Bot.) An infection of cereal grains producing a swelling
which is at length resolved into a powdery sooty mass. It
is caused by parasitic fungi of the genus {Ustilago}.
{Ustilago segetum}, or {Ustilago Carbo}, is the commonest
kind; that of Indian corn is {Ustilago maydis}.
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4. Obscene language; ribaldry; obscenity.
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He does not stand upon decency . . . but will talk
smut, though a priest and his mother be in the room.
--Addison.
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{Smut mill}, a machine for cleansing grain from smut.
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