Corrosion is the slow eating-away of metal by water, air, salt, or chemicals. Rust on iron is the picture most people know, but other metals corrode too, sometimes without that red-brown look. The word can mean the process, or the damaged stuff it leaves behind.

Corrosion is the slow eating-away of metalCorrosion是金屬慢慢被侵蝕的過程 by water, air, salt, or chemicals由水、空氣、鹽份或化學物質造成。Rust on iron is the picture most people know鐵生鏽是大家最熟悉的畫面，but other metals corrode too但其他金屬也會腐蝕，sometimes without that red-brown look有時候並不會有那種紅棕色的樣子。The word can mean the process這個字可以指過程，or the damaged stuff it leaves behind也可以指它留下來的受損物質。

It is the ordinary technical word in science and engineering; rust is the everyday word when the metal is iron.

It is the ordinary technical word in science and engineering它是科學和工程領域常用的專業字；rust is the everyday word when the metal is iron如果金屬是鐵，日常說法就是rust生鏽。

People also stretch it: they talk about the corrosion of trust or of public life, meaning something good is being slowly eaten away. That figurative use is still a bit formal.

People also stretch it大家也會延伸這個字：they talk about the corrosion of trust or of public life說the corrosion of trust（信任的腐蝕）或of public life（公共生活的腐蝕），meaning something good is being slowly eaten away意思是某個好的東西正被慢慢侵蝕掉。That figurative use is still a bit formal這種比喻用法還是偏正式。

Though actually, rust is only one kind of corrosion, so in a lab report you should not swap the two without thinking. A nearby word, erosion, is wearing away of land or rock by wind and water, not chemical attack on metal.

Though actually不過，rust is only one kind of corrosionrust只是corrosion的一種，so in a lab report you should not swap the two without thinking所以在實驗報告裡不能不假思索地把兩個字互換。A nearby word, erosion一個相近的字erosion，is wearing away of land or rock by wind and water指的是土地或岩石被風和水磨損的過程，not chemical attack on metal不是金屬受到化學侵蝕。