The origin of the name "assault rife" is none other than Adolf Hitler!
From Wikipedia:
The term assault rifle is a translation of the German word Sturmgewehr (literally "storm rifle", "storm" as in "military attack"). The name was coined by Adolf Hitler as a new name for the Maschinenpistole 43, subsequently known as the Sturmgewehr 44, the firearm generally considered the first assault rifle that served to popularize the concept and form the basis for today's modern assault rifles.
Military assault rifles have the ability to fire in either short bursts or continuously on one pull of the trigger until the magazine is exhausted. Civilian rifles are based on the design of an assault rifle but which can only fire one shot for each pull of the trigger are essentially sporting rifles. A military would never use them to assault a position defended by people who have assault rifles with automatic fire capability.
My experience with the AR-15s and similar assault rifles carried by our Highway Patrol and swat teams is that they have settings for single shot, 3 shots and continuous fire. In one incident I investigated the swat team had their AR's on the 3 shot setting. Continuous bursts can result in the waste of a lot of ammo if the rifle isn't held under tight control to minimize barrel climb on successive rounds. Even then, expecting all the rounds to hit lethal zones on a man size target is expecting a lot. It would take a LOT of practice and development of a particular set of muscles to achieve that kind of accuracy.