from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A substance used to reduce the hardness of water.
- n. A device that monitors and reduces the hardness of the water.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A device which reduces the calcium and magnesium concentration of hard water by passing it through an ion exchange resin.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a substance (such as sodium chloride) that lessens the hardness of water by replacing calcium and magnesium ions with sodium ions and so gives the water more efficient sudsing power
Sorry, no etymologies found.