The oxyanion of phosphorus P2O64- derived from hypophosphoric acid; any salt containing this anion(noun)
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Use "hypophosphate" in a sentence
"Warm baths, friction, and stimulating lotions and cosmetics may be here employed, together with a course of some mild chalbeate (as the lactate, protophosphate, or ammonia-citrate of iron) and hypophosphate of soda."