Retronym

A retronym is a newer name for something that differentiates it from something else that is newer and similar; thus, avoiding confusion between the two.

Etymology
The term retronym, a neologism composed of the combining forms retro- (from Latin retro, "before") + -nym (from Greek ónoma, "name"), was coined by Frank Mankiewicz in 1980 and popularized by William Safire in The New York Times Magazine.

In 2000 The American Heritage Dictionary (4th edition) became the first major dictionary to include the word retronym.

Examples


The global war from 1914 to 1918 was referred to at the time as the Great War. However, after the subsequent global war erupted in 1939, the phrase Great War was gradually deprecated. The first came to be known as World War I and the second as World War II.

The first bicycles with two wheels of equal size were called "safety bicycles" because they were easier to handle than the then-dominant style that had one large wheel and one small wheel, which then became known as an "ordinary" bicycle. Since the end of the 19th century, most bicycles have been expected to have two equal-sized wheels, and the other type has been renamed "penny-farthing" or "high-wheeler" bicycle.

The Atari Video Computer System platform was rebranded the "Atari 2600" (after its product code, CX-2600) in 1982 following the launch of its successor, the Atari 5200, and all hardware and software related to the platform were released under this new branding from that point on. Prior to that time, Atari often used the initialism "VCS" in official literature and other media, but colloquially the Video Computer System was often simply called "the Atari."

The first film in the Star Wars franchise, Star Wars, was released in 1977, was given the subtitle "Episode IV: A New Hope" in its 1981 theatrical re-release, shortly after the release of its sequel The Empire Strikes Back. Initially this subtitle was limited to the opening text crawl, as all three films in the original Star Wars trilogy (Star Wars, The Empire Strikes Back, and Return of the Jedi) were still sold under their original theatrical titles on home media formats (such as VHS and Laserdisc) until their 2004 DVD releases, in which the titles of the individual three films were changed to follow the same titling pattern as the Star Wars prequel trilogy (e.g. Star Wars Episode IV - A New Hope).

In the 1990s when the Internet became widely popular and email accounts' instant delivery common, mail carried by the postal service came to be called "snail mail" for its slower delivery and email sometimes just "mail."

Advances in technology are often responsible for the coinage of retronyms. For example, the term acoustic guitar was coined with the advent of the electric guitar, analog watch was introduced to distinguish from the digital watch, push bike was created to distinguish from the motorized bicycle, and feature phone was coined behind smartphone.