Wiktionary
n. (context firearms English) A device for loading a firearm or magazine with loose ammunition very quickly.
Wikipedia
A speedloader is a device used to reduce the time and/or effort needed to reload a firearm. Speed loaders come in variety of forms for reloading revolvers or with fixed (attached) or detachable magazines.
Generally, speedloaders are used for loading all chambers of a revolver simultaneously, although speedloaders (of different designs) are also used for the loading of fixed tubular magazines of shotguns and rifles, or (with other designs) the loading of box or drum magazines. Revolver speedloaders are used for revolvers having either swing-out cylinders or top-break cylinders. Non-top-break cylinder revolvers having fixed cylinders must be unloaded and loaded one chamber at a time.
Usage examples of "speedloader".
She ejected the round-point cartridges from her pistol and Speedloaders and replaced them with the new bullets -hollow points, which have more stopping power and cause much more damage to soft tissue when they hit a human being.