submachine gun(n = noun.artifact) - machine gun that is a portable automatic firearm;
is a kind of machine gun
has particulars: bren, bren gun, burp gun, machine pistol, kalashnikov, light machine gun, sten gun, thompson submachine gun, tommy gun, uzi

ack-ack gun, air gun, antiaircraft gun, assault gun, bb gun, big gun, bofors gun, bren gun, browning machine gun, burp gun, electron gun, field gun, gas gun, gatling gun, grease gun, gun, gun barrel, gun carriage, gun case, gun chamber, gun control, gun deck, gun dog, gun down, gun emplacement, gun enclosure, gun for, gun for hire, gun moll, gun muzzle, gun rest, gun room, gun smoke, gun trigger, gun turret, harpoon gun, high-angle gun, hired gun, hotchkiss gun, hydropneumatic gun carriage, jump the gun, krupp gun, light machine gun, machine gun, maxim gun, minute gun, naval gun, paintball gun, quaker gun, riot gun, set gun, smoking gun, spray gun, spring gun, squirt gun, staple gun, sten gun, stun gun, thompson submachine gun, tommy gun, vickers' gun, vickers-maxim automatic machine gun, vickers-maxim gun, water gun, whaling gun, whitworth gun, wire gun, wire-wound gun, zip gun