{ } n. (Min.) A glassy volcanic rock of a grayish color and pearly luster, often having a spherulitic concretionary structure due to the curved cracks produced by contraction in cooling. See Illust. under Perlitic. [ 1913 Webster ]
[amimechouchouuo](n) pearlscale butterflyfish (Chaetodon xanthurus, Western Pacific species found from Indonesia and the Philippines north to the Ryukyu Islands); Philippines chevron butterflyfish; orange butterflyfish; netted butterflyfish; yellow-tailed butterflyfish[Add to Longdo]