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.
Recent Examples on the Web: Noun The body uses silver powder coating for rust protection, and the stand’s head features a thick rubber pad to protect the car’s underside from potential dents and scratches. Talon Homer, Popular Mechanics, 17 June 2022 Simple Green is a popular brick-friendly cleaning product that can tackle oil, grease, or rust that builds up on locations like driveways. Kristina Mcguirk, Better Homes & Gardens, 16 June 2022 But Atlanta, having shaken off the rust, is in hot pursuit. New York Times, 13 June 2022 Now, the Rangers will have to prove it against the defending Stanley Cup champions, who have shaken off any doubt about rust or the mileage that comes with three playoff runs in 22 months. Sean Farrell, USA TODAY, 8 June 2022 Petzing didn’t address those throws specifically but noted that rust has been visible so far. Scott Patsko, cleveland, 8 June 2022 Obama, Rodden says, invested lots of time in small, rust-belt cities, winning Ohio twice and even carrying Indiana in 2008. Kara Miller, BostonGlobe.com, 1 June 2022 Brennan shook off the rust from missing the last 5 games. Dylan Bumbarger, oregonlive, 23 Apr. 2022 Like any loved classic car, this one has a couple of dents, a little rust, and some paint chips, scratches, and blemishes. Becca Hackett, Car and Driver, 21 Apr. 2022 Recent Examples on the Web: Verb Screens that will live mostly or totally outdoors often require more frequent washing and can rust more easily, so look for screens that specifically offer protection against outdoor elements in their descriptions. Rachel Simon, Better Homes & Gardens, 16 June 2022 It is made with 100% stainless steel that won’t rust or tarnish. Chris Hachey, BGR, 22 June 2021 Rosen holds his responsibility as a journalist higher than his love for his subject, sharing unflattering and sometimes bleak truths about bicycles that rust their shining image. Zoë Beery, The Atlantic, 31 May 2022 Red areas are due to rust mixtures, yellows are due to iron sulfide, purples are from goethite or oxidized limonite, and the greens come from chlorite. Stacey Leasca, Travel + Leisure, 12 May 2022 Metal and vinyl will resist weathering, but can potentially rust and develop leaks. Rena Behar, Better Homes & Gardens, 5 May 2022 Ball joints in the wiper module can rust, causing one or both wipers to fail, increasing the risk of a crash. CBS News, 1 Apr. 2022 With approximately 5000 miles on its odometer, this 911 Carrera 4S Cabriolet is in far too fine of shape to risk either rot or rust. Greg Fink, Car and Driver, 3 May 2022 Both promise to keep the box intact in rain or snow, and the materials used also mean the wood-look box won't rust, peel, or dent like some of its counterparts. Carly Totten, Better Homes & Gardens, 29 Mar. 2022 See More

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.

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

21 Jun 2022

Cite this Entry

“Rust.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rust. Accessed 2 Jul. 2022.

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More Definitions for rust

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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