"And maybe as a result we learned that “assault rifle” should refer to a fully automatic gun that sprays many rounds with one trigger squeeze, while the semiautomatic variations (like that Sig Sauer) discharge one shot per trigger pull; or that this distinction separates guns designed for military use from those typically available to civilians; or that a term such as “AR-15-style” often refers more to a gun’s appearance than any precisely agreed-upon set of specific technical features."