'Pyrites' definitions:

Definition of 'pyrites'

From: WordNet
noun
Any of various metallic-looking sulfides (of which pyrite is the commonest)

Definition of 'Pyrites'

From: GCIDE
  • Pyrite \Pyr"ite\, n.; pl. Pyrites. [Cf. F. pyrite. See Pyrites.] (Min.) A common mineral of a pale brass-yellow color and brilliant metallic luster, crystallizing in the isometric system; iron pyrites; iron disulphide. [1913 Webster]
  • Hence sable coal his massy couch extends, And stars of gold the sparkling pyrite blends. --E. Darwin. [1913 Webster]

Definition of 'Pyrites'

From: GCIDE