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1

rust

play
noun \ˈrəst\

Simple Definition of rust

  • : 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of rust

  1. 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. 2 :  corrosive or injurious influence or effect

  3. 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. 4 :  a strong reddish brown

Examples of rust in a sentence

  1. an old pump covered in rust



Origin and Etymology of rust

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


First Known Use: before 12th century


2

rust

verb

Simple Definition of rust

  • : to form rust : to become rusty

  • : to cause rust to form on (something)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of rust

  1. intransitive verb
  2. 1 :  to form rust :  become oxidized <iron rusts>

  3. 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>

  4. 3 :  to become reddish brown as if with rust <the leaves slowly rusted>

  5. 4 :  to be affected with a rust fungus

  6. transitive verb
  7. 1 :  to cause (a metal) to form rust <keep up your bright swords, for the dew will rust them — Shakespeare>

  8. 2 :  to impair or corrode by or as if by time, inactivity, or deleterious use

  9. 3 :  to cause to become reddish brown :  turn the color of rust

Examples of rust in a sentence

  1. Your bicycle will rust if you leave it out in the rain.

  2. The moist air rusted the latch on the door.

  3. The old iron fence was rusted.



13th Century

First Known Use of rust

13th century


RUST Defined for Kids

1

rust

play
noun \ˈrəst\

Definition of rust for Students

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

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

  3. 3 :  a fungus that causes a rust




2

rust

play
verb

Definition of rust for Students

rusted

rusting

  1. :  to make or become rusty




Medical Dictionary

rust

play
noun \ˈrəst\

Medical Definition of rust

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

  2. 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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