noun Date: 1870 a rock that consists largely of calcium phosphate usually together with other minerals (as calcium carbonate), is used in making fertilizers, and is a source of phosphorus compounds
PHOSPHATE ROCK
Meaning of PHOSPHATE ROCK in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012