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a. Any of various powdery or scaly reddish-brown or reddish-yellow hydrated ferric oxides and hydroxides formed on iron and iron-containing materials by low-temperature oxidation in the presence of water.
b. Any of various metallic coatings, especially oxides, formed by corrosion.
c. A stain or coating resembling iron rust.
2. Deterioration, as of ability, resulting from inactivity or neglect.
3. Botany
a. Rust fungus.
b. A plant disease caused by a rust fungus, characterized by reddish or brownish spots on leaves, stems, and other parts.
4. A strong brown.
v. rust·ed, rust·ing, rusts
1. To become corroded.
2. To deteriorate or degenerate through inactivity or neglect: My golf game has rusted from all those years of not playing.
3. To become the color of rust.
4. Botany To develop a disease caused by a rust fungus.
1. To corrode or subject (a metal) to rust formation.
2. To impair or spoil, as by misuse or inactivity.
3. To color (something) a strong brown.

[Middle English, from Old English rūst; see reudh- in Indo-European roots.]

rust adj.
rust′a·ble adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rusting - the formation of reddish-brown ferric oxides on iron by low-temperature oxidation in the presence of water
corroding, corrosion, erosion - erosion by chemical action
oxidation, oxidisation, oxidization - the process of oxidizing; the addition of oxygen to a compound with a loss of electrons; always occurs accompanied by reduction
ferric oxide - a red oxide of iron
References in classic literature ?
Some were fished from the bottom of the lake; some have been rusting in woods since the discovery of the country; and some were never guns at all--mere privateersmen's playthings
I remember a long gallery of rusting stands of arms, and how I hesitated between my crowbar and a hatchet or a sword.
It was now easy to yoke the bulls, and to harness them to the plow, which had lain rusting on the ground for a great many years gone by; so long was it before anybody could be found capable of plowing that piece of land.
A thousand swords, now rusting in ignoble sloth, shall leap from their scabbards to do battle for your honor against wrong.