rust

noun
\ ˈrəst How to pronounce rust (audio) \

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 After shaking off some rust, Chase emerged as a record-breaking star and leading candidate for Offensive Rookie of the Year while helping Cincinnati (10-7) get to the postseason for the first time since 2015. Tim Bielik, cleveland, 15 Jan. 2022 Rodgers will have to knock off the rust of not practicing for two weeks. Brad Biggs, chicagotribune.com, 9 Dec. 2021 Zach Wilson was back for the New York Jets, and so were the up-and-down moments of a rookie quarterback shaking off some rust. Dennis Waszak Jr., courant.com, 29 Nov. 2021 Shaking off the rust, developing new talent, tinkering with rosters and changing lineups can be worked out in the first month of the regular season. Lori Nickel, Milwaukee Journal Sentinel, 20 Oct. 2021 Marvel, too, at how the light refracted through the wine leaves a rust-colored patch of light on his shirt. Washington Post, 6 Oct. 2021 Hightower, back after opting out last season, had four tackles and zero impactful plays while shaking off the rust. BostonGlobe.com, 17 Sep. 2021 In July, the DA extradited from the United Kingdom a restorer who cleaned Kapoor’s antiquities, in part to hide dirt, rust, and other signs of their recent theft. Ariel Sabar, The Atlantic, 23 Nov. 2021 Like the return of Kyler Murray (without any apparent rust, with four touchdowns scored) to the starting lineup, and just in time for a difficult final slate that includes big games against the Rams (next week, Monday night), Colts and Cowboys. Jeremy Cluff, The Arizona Republic, 13 Dec. 2021 Recent Examples on the Web: Verb The foundation has settled in some areas of the buildings, causing water to intrude and metal to rust. Bob Sandrick, cleveland, 24 Dec. 2021 In addition, the team also made wooden nails that aren't prone to rust and can be nailed in with a hammer. Jordan Mendoza, USA TODAY, 27 Oct. 2021 Composite fuselages don't rust, and really don't age from pressurization and de-pressurization cycles. Chris Sloan, CNN, 26 Oct. 2021 The luster that accompanied the university’s hiring of Alabama offensive coordinator Steve Sarkisian as head coach already has started to rust. Nick Moyle, San Antonio Express-News, 25 Nov. 2021 Acne Studios rust orange/beige shearling jacket features a fur collar and two pockets, and is a versatile fall staple for any occasion. Joseph Deacetis, Forbes, 6 Nov. 2021 Lastly, if there are food bits that won't come off or rust, use kosher salt and a wet sponge and gently buff. Kaylei Fear, Better Homes & Gardens, 17 Nov. 2021 There are plentiful times that someone opts to park an old junk car on their front lawn and let the wreck gradually rust and stew. Lance Eliot, Forbes, 10 Oct. 2021 Made from surgical grade stainless steel, this is one of the best at-home razors for men that won’t ever rust. Chris Hachey, BGR, 23 Sep. 2021

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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Time Traveler for rust

Time Traveler

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

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Dictionary Entries Near rust

Russula

rust

rust belt

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Statistics for rust

Last Updated

28 Jan 2022

Cite this Entry

“Rust.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rust. Accessed 28 Jan. 2022.

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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 How to pronounce rust (audio) \

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 How to pronounce rust (audio) \

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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