shuttle

1. A tool used to carry the woof back and forth between the warp threads on a loom.
2. The sliding thread holder in a sewing machine, which carries the lower thread through a loop of the upper thread, to make a lock stitch.
3. A transport service (such as a bus or train) that goes back and forth between two or more places. · The shuttle bus runs to the airport on a half-hourly basis from the central station.
4. Such a transport vehicle; a shuttle bus; a space shuttle.
5. Any other item that moves repeatedly back and forth between two positions, possibly transporting something else with it between those points (such as, in chemistry, a molecular shuttle).
6. A shuttlecock.
7. A shutter, as for a channel for molten metal.

Plural shuttles