Rust

Part of speech: noun, verb

Pronunciation: /ɹʌst/

Definitions

1. A reddish-brown coating that forms on iron or steel when exposed to moisture and oxygen over time
2. A chemical degradation process that leads to the formation of a reddish-brown layer on metals due to prolonged exposure to moisture and air
3. A process in which iron or steel undergoes oxidation to develop a reddish-brown corrosion layer as a result of exposure to moisture and oxygen in the environment

Etymology: Rust is one of the few English words whose colour came before its name for the colour's cause. The Proto-Germanic root *rustaz is tied to the Indo-European root for "red," so the word for the flaky reddish coating on iron was built from the idea of redness itself. Its ancestors in Dutch, German, Swedish and Finnish all keep the same sense, which suggests the word was well established among the Germanic peoples long before English had its own version. Old English used "rust" for the corrosion of metal, and the same noun also appeared in a second sense: a blight or mildew that attacked plants and crops. The reddish, dusty look of diseased leaves gave the word its association with decay, and this older meaning explains why a withered leaf could be described as rusting. Like many everyday words from the early medieval period, "rust" passed through several spellings, including rost, rosst and roust, before settling into its modern form. The verb "to rust," meaning to corrode or become corroded, developed from the noun in Middle English.

Synonyms: corrosion, oxidation, decay, deterioration, wear

Antonyms: shine, luster, brightness, polish