Definition of galloper:
(n) :
A racehorse.
(n) :
One who gallops.
(n) :
An aide-de-camp.
(n) :
A carousel or roundabout (especially in the plural)
(n) :
(military) A carriage on which very small guns were formerly mounted, the gun resting on the shafts, without a limber.
(n) :
(Australia) The Chinamanfish, a type of snapper