D defs.my
Entry 1 sense Webster, 1913

Microcrystalline

· Mi·cro·crys·tal·line · IPA
01 a. Crystalline on a fine, or microscopic, scale; consisting of fine crystals; as, the ground mass of certain porphyrics is microcrystalline.
  1. 1.
    Crystalline on a fine, or microscopic, scale; consisting of fine crystals; as, the ground mass of certain porphyrics is microcrystalline.(Crystallog.)