/mahr"geuh ruyt'/ , n.
1. Mineral.
a. a gray, pink, or yellow mica, occurring in brittle monoclinic crystals.
b. an aggregate of small, rudimentary crystals resembling minute globules in a row: found in glassy volcanic rocks.
2. Obs. a pearl.
[ bef. 1000; ME, OE: pearl margarita margarítes, perh. marvarit pearl), with final element conformed to Gk -ites -ITE 1 ]