O"nyx (?), n. [L., fr. Gr. a claw, finger nail, a veined gem. See Nail, and cf. Onycha.] Min.
Chalcedony in parallel layers of different shades of color. It is used for making cameos, the figure being cut in one layer with the next as a ground.
Onyx marble, a banded variety of marble or calcium carbonate resembling onyx. It is obtained from Mexico.
© Webster 1913.