Definition of shuttles:
(n) :
A transport service (such as a bus or train) that goes back and forth between two or more places.
(n) :
Such a transport vehicle; a shuttle bus; a space shuttle.
(n) :
(weaving) A tool used to carry the woof back and forth between the warp threads on a loom.
(n) :
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.
(n) :
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).
(v) :
(intransitive, transitive) To go or send back and forth between two places.