RUST

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.

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.

That which resembles rust in appearance or effects. Specifically:

A composition used in making a rust joint. See Rust joint, below.

Foul matter arising from degeneration; as, rust on salted meat.

Corrosive or injurious accretion or influence. Sacred truths cleared from all rust and dross of human mixtures. Eikon Basilike.

To contract rust; to be become oxidized. If gold ruste, what shall iron do Chaucer. Our armors now may rust. Dryden.

To be affected with the parasitic fungus called rust; also, to acquire a rusty appearance. as plants.

Fig.: To degenerate in idleness; to become dull or impaired by inaction. Must I rust in Egypt never more Appear in arms, and be the chief of Greece Dryden.

To cause to contract rust; to corrode with rust; to affect with rust of any kind. Keep up your bright swords, for the dew will rust them. Shak.

Fig.: To impair by time and inactivity. Johmson.