The term XLR originated in the connector’s early days at Cannon Electric. “X” referred to the company’s particular series of connectors, with “L” specifying the presence of a latch mechanism, and “R” representing the use of a rubber compound. Some sources suggest XLR stands for “external line return,” but this is a misnomer that disregards the connector’s extensive use as a means of carrying audio signals of every type and nature.