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 The rust was evident for both teams in the first half. Dave Skretta, ajc, "No. 8 Texas tops No. 3 KU 84-59 to tie record margin at Phog," 2 Jan. 2021 To help prevent rust and corrosion, make sure your chain is lubricated with bicycle-specific lube or wax. New York Times, "You Got a Bicycle, Now You Have to Take Care of It," 25 Dec. 2020 Clean tools thoroughly and coat the metal with a light film of oil to prevent rust. Dan Gill, NOLA.com, "Garden tips: See which veggies to plant now; expect a little purple; and don't leave leaves down long," 2 Dec. 2020 That said, the rust of going three weeks without a game is something Herman said is worrisome. Dallas News, "Tom Herman sings praises of QB Sam Ehlinger, 2017 recruiting class heading into Texas’ senior day," 23 Nov. 2020 Today’s stainless are nearly as slick and smooth as the best chrome-moly with the bonus of minimizing rust. Ron Spomer, Outdoor Life, "How to Buy Your First Nice Hunting Rifle," 2 Nov. 2020 His rust was evident as his passes often missed their marks. Mike Jones, USA TODAY, "Opinion: Returning to the field two years after gruesome injury, Alex Smith proves triumphant even in Washington loss," 12 Oct. 2020 With Wilson returning from more than a year spent rehabbing from a season-ending knee injury, rust was always a concern for UK’s early games this season. Jon Hale, The Courier-Journal, "Pressure on UK receivers to step up with possible shootout coming vs. Ole Miss," 30 Sep. 2020 Rust converters actually change the chemical composition of the rust. Bob Beacham, chicagotribune.com, "The best rust prevention spray," 12 Dec. 2020 Recent Examples on the Web: Verb Parkerizing also aims to rust-proof iron or steel by dunking parts in a hot acidic solution. Natalie Krebs, Outdoor Life, "The Evolution of Shotgun Coatings: From Blued Barrels to (Mostly) Impervious Firearm Finishes," 11 Jan. 2021 Bright finish is easy to keep clean and won't rust. Bob Beacham, chicagotribune.com, "The best shave kit," 22 Dec. 2020 This variety became a favorite of customers in salty-aired Hawaii and Bahamas because glass doesn’t rust or corrode due to air quality. Jennifer Billock, Smithsonian Magazine, "Only One Factory in North America Still Makes Washboards, and They Are Flying Off of Shelves," 11 Nov. 2020 An amphibious winch with a synthetic rope that won't corrode or rust is a great addition to any vehicle pressed into hard service in chronically muddy or boggy environments. The Editors, Outdoor Life, "3 Features to Consider Before You Buy an Electric Winch," 23 Oct. 2019 Lightweight ball bearing reel with aluminum spool that won't rust. Bob Beacham, chicagotribune.com, "The best ice fishing rod," 17 Oct. 2020 Moisture can causemoving parts to rust and seize up. Peter Krouse, cleveland, "Tips for storing your bicycle this winter," 17 Oct. 2020 The Aurora’s luster had largely faded when Willson got his first look, rust and rot taking hold. Kurtis Alexander, San Francisco Chronicle, "Shipwrecked on Little Potato Slough," 8 Oct. 2020 The metal will rust if it’s not wiped down with a thin layer of oil after washing. Paul Stephen, ExpressNews.com, "Paul’s Cooking Tips: How to use a paella pan for biscuits, stir fry, roasting chicken and more," 26 Sep. 2020

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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Statistics for rust

Last Updated

16 Jan 2021

Cite this Entry

“Rust.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rust. Accessed 22 Jan. 2021.

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More Definitions for rust

rust

noun
How to pronounce rust (audio)

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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Comments on rust

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