1. A hard black form of lignite that takes a brilliant polish and is used in jewellery or ornamentation.
2. An airplane powered by one or more jet engines; SYN. jet plane, jet-propelled plane.
3. The occurrence of a sudden discharge (as of liquid); SYN. squirt, spurt, spirt.
Hard, black variety of lignite, a type of coal. It is cut and polished for use in jewelry and ornaments. Articles made of jet have been found in Bronze Age tombs