A backronym (or bacronym) is a 'reverse acronym', that is a definition constructed "after the fact" to make an already existing word or words into an acronym.
Backronyms may be invented with humorous intent, or may be a type of false or folk etymology. The word is a portmanteau term combining back and acronym, first cited in a 1983 Washington Post column - "A bacronym ... is the 'same as an acronym, except that the words were chosen to fit the letters.' "[1]
An "acronym" is a pronounceable word derived from the initial letters of a phrase:[2] For example, the word radar comes from "Radio Detection and Ranging".[3] Letters from the originating phrase are used to construct a pronounceable word.
By contrast, a backronym is constructed by starting with a word and, beginning with the first letter, using the letters to begin each word of a phrase. The word then becomes an acronym or initialism of the newly formed phrase. In this sense, a backronym is the reversal of an acronym.
Since an acronym is defined as a word,[4] and a backronym is constructed from an acronym, it logically follows that the phrase must come from a word. However, this rule is commonly broken, even by dictionaries providing examples such as DVD (an initialism, see image)[5] and SOS (a representation of the emergency signal used in Morse code).[4]
Backronyms can be classified along various types.[citation needed] Note that these types are not necessarily exclusive of each other, that is, a backronym could fit into more than one type.
Many backronyms are apronyms, that is, the word itself is relevant to its associated phrase.[6] The relevance may be either serious or ironic.
A pure backronym occurs when the root word was not previously or commonly known as an acronym. Examples:
Backronyms can be constructed for educational purposes, for example to form mnemonics so that the word or initialism is easier to remember.
An example of such a mnemonic is the Apgar score, used to assess the health of newborn children. The rating system is named after Virginia Apgar, but ten years after the initial publication, the backronym APGAR[9] was coined in the US as a mnemonic learning aid: Appearance (skin color), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone), and Respiration.
Alcoholics Anonymous and other 12 step programs have a verbal culture that makes extensive use of backronyms[10]. They're used as teaching tools, similar to slogans like "one day at a time," or "Let go, let God," but often have an ironic edge.
Sometimes the backronym is so commonly heard, that it is generally but incorrectly believed to have been used in the formation of the word, and amounts to a folk etymology. Examples of these include:
((cite web)): Text "perl.org" ignored (help)) According to "Perl documentation". ((cite web)): Text "perl.org" ignored (help), Perl is not an acronym.