rust
part of speech
noun (rust — uncountable); verb (rust, rusts, rusted, rusting)
meaning for a pupil
1) Rust is the reddish-brown, flaky coating that forms on iron or steel when it gets wet and meets air. tree →
2) To rust means to become covered with rust. tree →
3) Rust is also a reddish-brown colour. tree →
sense in the lessons
In science rust is a chemical change: iron reacts with oxygen and water, so it is a classic example of a change you cannot undo. In everyday life it makes bikes, nails and gates weak; paint and oil stop it. Phrases: «rust away», «covered in rust», «rust-proof», «rusty».
examples
- My old bike chain is covered in rust. tree →
- Iron rusts when it is left out in the rain. tree →
- Paint stops the gate from rusting. tree →
- Rust made the metal weak and it broke. tree →
- Be careful with rusty nails; they can cut you. tree →
- The car had rust on its doors. tree →
- Salt water makes metal rust faster. tree →
- Gold never rusts. tree →
- Others polished the blade until all the rust was removed and it glistened like burnished silver. tree →
note
Uncountable: some rust, not «a rust». Adjective: rusty. Only iron and steel truly rust; other metals tarnish or corrode. Safety: a cut from a rusty nail needs cleaning and maybe a tetanus shot — the danger is germs (tetanus), not the rust itself.
In the corpora
- When atoms change partners, a new substance appears, which is what happens when a nail slowly rusts in water.
- Rust forms when iron atoms join with oxygen and water, and a rusted nail weighs more than the clean nail.
- That orange stuff is rust, a brand-new substance, not dirt that has landed on the metal.
- Take away either one, the water or the oxygen, and the iron hardly rusts at all.
- In a hand-warmer pack the iron is a fine powder, so it rusts fast enough for you to feel the warmth.
Trees and pragmatics
Every meaning and example of «rust» parsed by Mova, each sentence with its dependency tree and frames.