From The Collaborative International Dictionary of English v.0.48:
Rust \Rust\, v. t.
1. To cause to contract rust; to corrode with rust; to affect
with rust of any kind.
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Keep up your bright swords, for the dew will rust
them. --Shak.
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2. Fig.: To impair by time and inactivity. --Johnson.
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From The Collaborative International Dictionary of English v.0.48:
Rust \Rust\, n. [AS. rust; akin to D. roest, G. & Sw. rost,
Icel. ry[eth]; -- named from its color, and akin to E. red.
[root]113. See Red.]
1. (Chem.) The reddish yellow coating formed on iron when
exposed to moist air, consisting of ferric oxide or
hydroxide; hence, by extension, any metallic film of
corrosion.
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2. (Bot.) A minute mold or fungus forming reddish or rusty
spots on the leaves and stems of cereal and other grasses
(Trichobasis Rubigo-vera), now usually believed to be a
form or condition of the corn mildew (Puccinia
graminis). As rust, it has solitary reddish spores; as
corn mildew, the spores are double and blackish.
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Note: Rust is also applied to many other minute fungi which
infest vegetation, such as the species of Ustilago,
Uredo, and Lecythea.
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3. That which resembles rust in appearance or effects.
Specifically: (a) A composition used in making a rust
joint. See Rust joint, below.
(b) Foul matter arising from degeneration; as, rust on
salted meat.
(c) Corrosive or injurious accretion or influence.
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Sacred truths cleared from all rust and dross of
human mixtures. --Eikon
Basilike.
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Note: Rust is used in the formation of compounds of obvious
meaning; as, rust-colored, rust-consumed, rust-eaten,
and the like.
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Rust joint, a joint made between surfaces of iron by
filling the space between them with a wet mixture of
cast-iron borings, sal ammoniac, and sulphur, which by
oxidation becomes hard, and impervious to steam, water,
etc.
Rust mite (Zool.), a minute mite (Phytopius oleivorus)
which, by puncturing the rind, causes the rust-colored
patches on oranges.
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From The Collaborative International Dictionary of English v.0.48:
Rust \Rust\, v. i. [imp. & p. p. Rusted; p. pr. & vb. n.
Rusting.] [AS. rustian.]
1. To contract rust; to be or become oxidized.
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If gold ruste, what shall iron do? --Chaucer.
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Our armors now may rust. --Dryden.
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2. To be affected with the parasitic fungus called rust;
also, to acquire a rusty appearance, as plants.
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3. Fig.: To degenerate in idleness; to become dull or
impaired by inaction.
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Must I rust in Egypt? never more
Appear in arms, and be the chief of Greece?
--Dryden.
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From The Collaborative International Dictionary of English v.0.48:
Ferrugo \Fer*ru"go\ (f[e^]r*r[udd]"g[-o]), n. [L., iron rust,
fr. ferrum iron.]
A disease of plants caused by fungi, commonly called the
rust, from its resemblance to iron rust in color.
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