aphanite

From Ancient Greek ἀφανής (aphanḗs, “indistinct, unseen, obscure”) +‎ -ite.

• IPA^(key): /ˈæf.əˌnaɪt/

aphanite (countable and uncountable, plural aphanites)

1. (geology, petrology) Certain dark igneous rocks having grain so fine that the individual crystals cannot be seen with the naked eye.

   Antonym: phanerite

• aphanite in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913
• “aphanite”, in The Century Dictionary […], New York, N.Y.: The Century Co., 1911, →OCLC.
• aphanite at OneLook Dictionary Search