A water softener is a device or substance which removes certain minerals, for example calcium, from water, so that it makes bubbles easily when you use soap to wash things.
N-MASS
织物软化剂，柔顺剂(洗衣时加入水中的一种化学物质，可使衣物手感柔和)
A fabric softener is a chemical substance that you add to water when you wash clothes in order to make the clothes feel softer.
英英词典释义
Noun
1. a substance added to another to make it less softer