A retronym is a type of neologism coined for an old object or concept whose original name has come to be used for something else or is no longer unique. Retronym is a neologism coined by Frank Mankiewicz [1] and popularized by William Safire [2] in 1980 in the New York Times. Many of these are created by advances in technology. However, a retronym itself is a neological word coinage consisting of the original noun with a different adjective added, which emphasises the distinction to be made from the original form.
In 2003, the American Heritage Dictionary was the first major dictionary to include the word retronym.[3]
Examples of retronyms are acoustic guitar - coined when electric guitars appeared, or Parallel ATA - necessitated by the introduction of Serial ATA as a term for the original ATA.
Posthumous names awarded in East Asian cultures to royalty after their death can be considered retronyms too, although their birth names will remain unambiguous.
Careless anachronistic use of a retronym can break the suspension of disbelief in historical fiction. Anachronistic use of a retronym could also betray a modern document forgery (such as a description of the First Battle of Bull Run before the second had taken place).