society > armed hostility > military equipment > weapon > fire, radiation, or chemical weapons > [noun] > guns discharging water (3)
Apparently: a device for shooting water, intended for use in firefighting. Cf. water cannon n. at water, n. compounds 7. Obsolete.
a device for ejecting a powerful jet of water, originally used as a mining tool, later also in firefighting and as a means of dispersing crowds.
a toy pistol that shoots a jet of water; (occasionally more generally) any pistol capable of discharging water or other liquid.