rust

Rust is the reddish-brown stuff that forms over time on metal that's gotten wet. Your dad's beat-up old car probably has some rust on it somewhere.

If you leave your bike out overnight in the rain, it'll be fine — you can dry it off the next day. If you leave it out for several rainy weeks, though, your bike will end up with rust on it. Rust appears as brown spots where the combination of water and oxygen has coated the metal with a compound that chemists call an oxide. Rust, which is also a verb, comes from a Germanic root meaning "redness."

Primary Meanings of rust

1.
nvadj
a red or brown oxide coating on iron or steel caused by the action of oxygen and moisture
become destroyed by water, air, or a corrosive such as an acid
of the brown color of rust
2.
n
any of various fungi causing rust disease in plants
Full Definitions of rust
1

n a red or brown oxide coating on iron or steel caused by the action of oxygen and moisture

Type of:
ferric oxide
a red oxide of iron

n the formation of reddish-brown ferric oxides on iron by low-temperature oxidation in the presence of water

Synonyms:
rusting
Type of:
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

v become destroyed by water, air, or a corrosive such as an acid

“The pipes rusted
Synonyms:
corrode
corrode, eat
cause to deteriorate due to the action of water, air, or an acid
Types:
eat away, fret
wear away or erode
Type of:
crumble, decay, dilapidate
fall into decay or ruin

v become coated with oxide

Synonyms:
oxidate, oxidise, oxidize
add oxygen to or combine with oxygen
Type of:
oxidate, oxidise, oxidize
enter into a combination with oxygen or become converted into an oxide

v cause to deteriorate due to the action of water, air, or an acid

“The steady dripping of water rusted the metal stopper in the sink”
Synonyms:
corrode, eat
corrode
become destroyed by water, air, or a corrosive such as an acid
Type of:
damage
inflict damage upon

adj of the brown color of rust

Synonyms:
rust-brown, rusty
chromatic
being or having or characterized by hue
2

n any of various fungi causing rust disease in plants

Synonyms:
rust fungus
Types:
show 4 types...
hide 4 types...
Melampsora lini, flax rust, flax rust fungus
fungus causing flax rust
Cronartium ribicola, blister rust
fungus causing white pine blister rust and having a complex life cycle requiring a plant of genus Ribes as alternate host
Puccinia graminis, wheat rust
rust fungus that attacks wheat
Gymnosporangium juniperi-virginianae, apple rust, cedar-apple rust
rust fungus causing rust spots on apples and pears etc
Type of:
fungus
an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytia

n a plant disease that produces a reddish-brown discoloration of leaves and stems; caused by various rust fungi

Types:
blister rust, white pine blister rust, white-pine rust
any of several diseases of pines caused by rust fungi of the genus Cronartium and marked by destructive invasion of bark and sapwood and producing blisters externally
Type of:
plant disease
a disease that affects plants

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