| soft water n. Water containing little or no dissolved salts of calcium or magnesium, especially water containing less than 85.5 parts per million of calcium carbonate. |
soft water
water that is free from dissolved salts of such metals as calcium, iron, or magnesium, which form insoluble deposits such as appear as scale in boilers or soap curds in bathtubs and laundry equipment. See also hard water.
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