rust

noun
\ˈrəst \

Definition of rust 

(Entry 1 of 2)

1a : the reddish brittle coating formed on iron especially when chemically attacked by moist air and composed essentially of hydrated ferric oxide

b : a comparable coating produced on a metal other than iron by corrosion

c : something resembling rust : accretion

2 : corrosive or injurious influence or effect

3 : any of numerous destructive diseases of plants produced by fungi (order Uredinales) and characterized by usually reddish-brown pustular lesions also : a fungus causing this

4 : a strong reddish brown

rust

verb
rusted; rusting; rusts

Definition of rust (Entry 2 of 2)

intransitive verb

1 : to form rust : become oxidized iron rusts

2 : to degenerate especially from inaction, lack of use, or passage of time most men would … have allowed their faculties to rust— T. B. Macaulay

3 : to become reddish brown as if with rust the leaves slowly rusted

4 : to be affected with a rust fungus

transitive verb

1 : to cause (a metal) to form rust keep up your bright swords, for the dew will rust them— William Shakespeare

2 : to impair or corrode by or as if by time, inactivity, or deleterious use

3 : to cause to become reddish brown : turn the color of rust

Examples of rust in a Sentence

Noun

an old pump covered in rust

Verb

Your bicycle will rust if you leave it out in the rain. The moist air rusted the latch on the door. The old iron fence was rusted.
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Recent Examples on the Web: Noun

Often earthy natural colors in shade of rust, green, and browns. Lilah Ramzi, Vogue, "How to Throw an End of Summer Garden Party, From London’s Favorite Eat-In Flower Shop," 3 Aug. 2018 Elliott, the Flyers hope, shook off the rust in his 4-3 win Thursday over Carolina. Sam Carchidi, Philly.com, "Flyers want to win their way into Stanley Cup playoffs by beating Rangers," 6 Apr. 2018 For five innings, the rookie kept pace with Kershaw, who showed the opposite of rust. Dennis Lin, sandiegouniontribune.com, "Lamet impresses, but Kershaw dominates in shutout," 1 Sep. 2017 So Syngenta is pioneering the next giant step in drone technology: Software that identifies the precise rust, virus, or infestation, and sends instructions detailing the best treatment. Shawn Tully, Fortune, "This Agriculture Giant Is Bringing in the Drones to Modernize Farming From Cornfields to Vineyards," 19 June 2018 Despite the rust from not having played in eight months, Guerrero netted twice, sending his compatriots into a frenzy. Simeon Tegel, Washington Post, "Peru’s long-awaited World Cup party hits frenzy with return of Paolo Guerrero," 15 June 2018 On the second Carolina goal, Sebastian Aho skated out from behind the net and backhanded the puck off Elliott’s back and into the net, taking advantage of the rust that the Flyers’ 32-year-old goaltender readily admitted afterward was there. Sam Donnellon, Philly.com, "Flyers coach Dave Hakstol seems set to keep Brian Elliott in goal | Sam Donnellon," 6 Apr. 2018 But the rust was considerable, as Porter made just five of 17 field goal attempts and didn’t look real comfortable at times with the speed of the game or with his shooting rhythm in the framework of a halfcourt offense. Dan Wolken, USA TODAY, "Missouri's Michael Porter Jr. rusty in return, and expecting more might be too much to ask," 8 Mar. 2018 Her strokes have some rust and her timing, in New York, wasn’t quite right. Tom Perrotta, WSJ, "Serena Williams on Giving Birth, Her Health Scare and Coming Back," 7 Mar. 2018

Recent Examples on the Web: Verb

In this case, the film showcases a future that looks plenty familiar in anime and science fiction novels: a cluttered, rusted-out world that’s a little cyberpunk, a little steampunk, and a whole lot of classic anime series like Mobile Suit Gundam. Tasha Robinson, The Verge, "The Verge fall movie preview, December 2018," 7 Sep. 2018 This helps keep the bearings from pitting and the internal parts of the engine from rusting. Seth Porges, Popular Mechanics, "8 Clever Uses for Silica Gel," 29 Apr. 2010 Residents who have reddish brown water may have pipes or water heaters that are rusting. Michael Livingston, latimes.com, "Water quality report offers solutions to inconvenient troubles," 11 July 2018 Sorry in advance if these vehicles depreciate in value just as quickly as that Pontiac Aztek rusting away in your driveway. Nathan Bomey, USA TODAY, "10 hot vehicles most likely to increase in value, 'terrifying the neighbors'," 22 Apr. 2018 The number of hours that have been used on it are higher than normal, and some of the areas on the frame started to rust and have become unsafe. John Benson, cleveland.com, "North Olmsted spending $315,000 for new Service Department vehicle purchases," 7 Mar. 2018 The truck was rusted and appeared to have been in several wrecks. Jose R. Gonzalez, Houston Chronicle, "Louisiana authorities release facial reconstruction of severed head with similarities to HPD case," 27 June 2018 Inside was a collection of folded papers held together by disintegrating rubber bands and rusting staples. New York Times, "Found: Rosa Parks’s Arrest Warrant, and More Traces of Civil Rights History," 26 June 2018 But the pieces had sat out in the rain at the side of the highway for several days and had rusted. Meg Jones, Milwaukee Journal Sentinel, "Nightmare #1: Husband's death by flying debris on I-94. Nightmare #2: The investigation," 29 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rust.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of rust

Noun

before the 12th century, in the meaning defined at sense 1a

Verb

13th century, in the meaning defined at intransitive sense 1

History and Etymology for rust

Noun

Middle English, from Old English rūst; akin to Old English rēad red — more at red

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Statistics for rust

Last Updated

14 Nov 2018

Look-up Popularity

Time Traveler for rust

The first known use of rust was before the 12th century

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More Definitions for rust

rust

noun

English Language Learners Definition of rust

 (Entry 1 of 2)

: a reddish substance that forms on iron or some other metal usually when it comes in contact with moisture or air

: a disease that causes plants to develop reddish-brown spots

: a reddish-brown color

rust

verb

English Language Learners Definition of rust (Entry 2 of 2)

: to form rust : to become rusty

: to cause rust to form on (something)

rust

noun
\ˈrəst \

Kids Definition of rust

 (Entry 1 of 2)

1 : a reddish coating formed on metal (as iron) when it is exposed especially to moist air

2 : a plant disease caused by fungi that makes spots on plants

3 : a fungus that causes a rust

rust

verb
rusted; rusting

Kids Definition of rust (Entry 2 of 2)

: to make or become rusty

rust

noun
\ˈrəst \

Medical Definition of rust 

1 : the reddish brittle coating formed on iron especially when chemically attacked by moist air and composed essentially of hydrated ferric oxide

2 : any of numerous destructive diseases of plants produced by fungi (order Uredinales) and characterized by reddish brown pustular lesions also : a fungus causing this

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Comments on rust

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