noun
: a powdery impure form of tricalcium phosphate of low fertilizer value occurring in natural deposits of phosphate rock and separated from hard rock and pebble phosphates in fertilizer manufacture
noun
: a powdery impure form of tricalcium phosphate of low fertilizer value occurring in natural deposits of phosphate rock and separated from hard rock and pebble phosphates in fertilizer manufacture
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012