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.

Roget 356a: resin, rosin; gum; lac, sealing wax; amber, ambergris; bitumen, pitch, tar; asphalt, asphaltum; camphor; varnish, copal^†, mastic, magilp^†, lacquer, japan.    artificial resin, polymer; ion-exchange resin, cation-exchange resin, anion exchange resin, water softener, Amberlite^†, Dowex [Chem], Diaion.    ... show more

Dutch: waterverzachter