1.  assault gun(n = noun.artifact) assault rifle - any of the automatic rifles or semiautomatic rifles with large magazines designed for military use;
is a kind of automatic, automatic rifle, machine rifle

2.  assault gun(n = noun.artifact) - an armored vehicle with the chassis of a tank (but no turret) and a large gun; used as an antitank weapon and to support infantry;
is a kind of armored vehicle, armoured vehicle

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