Onyx has multiple meanings, including a gemstone, a sedimentary rock, and a computer utility.

Gemstone

A semiprecious gemstone with parallel bands of color, typically black and white, that's a variety of chalcedony, a silicate mineral. Onyx is often used in jewelry and carved into cameos and intaglios. It's moderately hard, with a rating of 6.5 to 7 on the Mohs scale of mineral hardness.

Sedimentary rock

A translucent rock that forms in caves as stalactites and stalagmites. The size and uniformity of the crystals in onyx contribute to its translucent properties.

Computer utility

A multifunction utility from Titanium Software that can verify system files, run maintenance tasks, and more.

Greek folklore

In ancient Greek folklore, onyx is said to have come from the fingernails of the goddess of love, Venus.

Raw, mined Onyx.