rust

1 of 2

noun

1
a
: 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

2 of 2

verb

rusted; rusting; rusts

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 rustT. 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 themWilliam 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
Store the cast iron pan in a dry place to prevent moisture from accumulating and causing rust. Maryal Miller Carter, USA TODAY, 21 Mar. 2024 In too-wet growing environments, diseases such as Botrytis blight (gray mold), root and stem rot, and rust are possible. Derek Carwood, Better Homes & Gardens, 18 Mar. 2024 Repairs have included more than $3 million for rust and hull repairs, and $3.35 million for bulkhead repairs and removing lifeboats. Salvador Hernandez, Los Angeles Times, 14 Mar. 2024 There are 13 colorways to choose from, ranging from the monochrome black, white, gray, and khaki combinations that are perfect for lovers of chic neutrals, while the green, rust, teal, and plum might blend in better with a wardrobe of bold colors. Olivia Young, Travel + Leisure, 6 Mar. 2024 The monument needs to be regularly stripped of old paint and given a fresh coat to prevent rust and other forms of deterioration. Aurelien Breeden, New York Times, 22 Feb. 2024 Ashley Childers had 11 points for Los Gatos, which fell to 23-4. North Coast Section Open Division boys No. 1 Salesian 60, No. 4 San Ramon Valley 45: Salesian showed no signs of rust after going 11 days in between games. Joseph Dycus, The Mercury News, 22 Feb. 2024 For rust and gunk, soak the handheld can opener or the removable cutting wheel of an electric can opener in vinegar for a few minutes. Kaitlyn Yarborough, Southern Living, 27 Feb. 2024 Set in ’80s New York, the dialogue-free film — which will have a U.S. theatrical release in May — tracks the ups and downs of this friendship through dance numbers to Earth, Wind & Fire and hardships like rust. Esther Zuckerman, The Hollywood Reporter, 21 Feb. 2024
Verb
Stewart recommends camellia oil, a Japanese oil extracted from the seed of a flowering shrub, to lubricate moving parts of tools and protect them from rusting with a preventative coating. Halee Miller, Better Homes & Gardens, 22 Mar. 2024 Offshoring turned thriving industrial centers to rust. TIME, 18 Mar. 2024 Stainless is reactive and free iron that sits on it will rust. Bryan Hood, Robb Report, 22 Feb. 2024 The blades are stainless steel and are designed not to rust, which is a bonus, because the grater is also dishwasher safe. Belle Duchene, Better Homes & Gardens, 8 Feb. 2024 But, cement erodes, paint fades, metal starts to rust. Debra Skodack, Kansas City Star, 7 Feb. 2024 But when that car started rusting, it was taken down, and a police cruiser donated by GM in 1995 went up in its place. Miami Herald Archives, Miami Herald, 5 Feb. 2024 Luke estimates the railing that fell probably started rusting five to eight years ago. Julia Daye, Sacramento Bee, 2 Feb. 2024 The derelict rail bridge stretches across a busy north London street, green foliage peeking out of the gaps between the beams overhead, where bright blue paint flakes from rusting steel. Megan Specia, New York Times, 27 Jan. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'rust.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

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

First Known Use

Noun

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

Verb

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

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

Dictionary Entries Near rust

Cite this Entry

“Rust.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rust. Accessed 29 Mar. 2024.

Kids Definition

rust

1 of 2 noun
1
: a reddish brittle coating formed on iron especially when chemically attacked by moist air and composed chiefly of ferric oxide
2
a
: any of numerous destructive diseases of plants caused by fungi and characterized by reddish brown spots
b
: any of an order of fungi that cause plant rusts
3
: a reddish brown

rust

2 of 2 verb
: to form or cause to form rust
iron rusts

Medical Definition

rust

noun
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
Last Updated: - Updated example sentences
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