Often, at first, the new version of an object is given a special name to distinguish it from the established version. If, however, the new version becomes the standard, it loses the part of its name that identifies it as new or different, and a retronym is coined for the original.
The earliest razors with encased blades were called “safety razors” to distinguish them from what were then just called “razors.” But the safety razor has since become the standard and the original razor is now called a “straight,” “open,” or “cut-throat” razor.
- Retronym, Wikipedia
