jet definition

1. an airplane powered by one or more jet engines
2. the occurrence of a sudden discharge (as of liquid)
3. a hard black form of lignite that takes a brilliant polish and is used in jewelry or ornamentation
4. atmospheric discharges (lasting 10 msec) bursting from the tops of giant storm clouds in blue cones that widen as they flash upward
5. issue in a jet; come out in a jet; stream or spring forth
• examples: Water jetted forth
• examples: flames were jetting out of the building
6. fly a jet plane