Retronym

A retronym is a neologism for a word created to differentiate between two words, where previously no clarification was required.

Advances in technology are often responsible for the coinage of retronyms. For example, the term "acoustic guitar" was coined at the advent of electric guitars and analog watches were thus named to distinguish them from digital watches.

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.

With the increasing discussion and legalization of same-sex marriage in the 20th and 21st centuries, terms such as "straight marriage" and "heterosexual marriage" arose to distinguish a set of unions which the term "marriage" had previously meant by default. Similarly, the term cisgender was coined to describe persons who identify with the gender they were assigned at birth.

The term retronym 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.

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