calcium phosphate

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A white amorphous powder, Ca₃(PO₄)₂, used in ceramics, rubber, fertilizers, and plastic stabilizers and as a food supplement.
• noun A dibasic white crystalline powder, CaHPO₄, used as an animal food, as a plastic stabilizer, and in glass and toothpaste.
• noun A monobasic colorless deliquescent powder, Ca(H₂PO₄)₂, used in baking powders, as a plant food, as a plastic stabilizer, and in glass.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun inorganic chemistry The calcium salt or phosphoric acid, Ca3(PO4)2, or of several related acids; it is the main mineral of bone

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a phosphate of calcium; a main constituent of animal bones