apatite

n. mineral

Not to be confused with appetite, the desire to eat. Apatite is a group of phosphate minerals, usually referring to hydroxylapatite, fluorapatite, and chlorapatite, named for high concentrations of OH-, F-, or Cl- ions, respectively, in the crystal. The formula of the admixture of the three most common endmembers is written as Ca5(PO₄)3(OH, F, Cl), and the formulae of the individual minerals are written as Ca5(PO4)3(OH), Ca5(PO4)3F and Ca5(PO4)3Cl, respectively.
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Noun
1. a common complex mineral consisting of calcium fluoride phosphate or calcium chloride phosphate; a source of phosphorus
(hypernym) mineral
(hyponym) fluorapatite
(substance-meronym) phosphorus, P, atomic number 15

n. apatite, mineral

(n.)
Native phosphate of lime, occurring usually in six-sided prisms, color often pale green, transparent or translucent.