—n. 1. a device in a loom for passing or shooting the weft thread through the shed from one side of the web to the other, usually consisting of a boat-shaped piece of wood containing a bobbin on which the weft thread is wound.
2. the sliding container that carries the lower thread in a sewing machine.
3. a public conveyance, as a train, airplane, or bus, that travels back and forth at regular intervals over a particular route, esp. a short route or one connecting two transportation systems.
4. shuttlecock (def. 1).
5. (often cap.) See space shuttle.
—v.t. to cause (someone or something) to move to and fro or back and forth by or as if by a shuttle: They shuttled me all over the seventh floor.
—v.i. to move to and fro: constantly shuttling between city and suburb.