We should refer to ARs as semi auto rifles, which is what they are, but as far as the media, most non gun people, all the antis, and many of us, they'll continue to call then assault rifles.
We can never go back and stop the use of the incorrect use of the term, but we should still call them semi autos.
Many call them that through ignorance, but the antis, at least one in this thread, and the anti friendly media will continue to attempt to stir up emotion/anti gun sentiment/votes with the scary term Assault Rifle.