"Assault rifle" has a very specific meaning: an intermediate-caliber, magazine-fed military rifle capable of both semi-automatic and automatic fire. That common meaning has been more or less fixed since WWII when it was adopted from the German word Sturmgewehr.
"Assault weapon" is a legal term that is defined by law (e.g., California's assault weapons ban or the failed federal Assault Weapons Ban of 2019 that you cited). "Assault weapon" includes not only semi-automatic rifles, but also shotguns and pistols that have certain characteristics. The definitions are long and complicated because they attempt to ban only weapons having the visual and ergonomic features of military weapons, while ignoring weapons of similar caliber that do not have those features.
"Assault rifle" has a very specific meaning: an intermediate-caliber, magazine-fed military rifle capable of both semi-automatic and automatic fire. That common meaning has been more or less fixed since WWII when it was adopted from the German word Sturmgewehr.
"Assault weapon" is a legal term that is defined by law (e.g., California's assault weapons ban or the failed federal Assault Weapons Ban of 2019 that you cited). "Assault weapon" includes not only semi-automatic rifles, but also shotguns and pistols that have certain characteristics. The definitions are long and complicated because they attempt to ban only weapons having the visual and ergonomic features of military weapons, while ignoring weapons of similar caliber that do not have those features.