The term idiolect refers to the language of an individual. It is etymologically related to the Greek prefix idio- (meaning "own, personal, private, peculiar, separate, distinct") and a back-formation of dialect.
The notion of language is used as an abstract description of the language use, and of the abilities of individual speakers and listeners.[better source needed] According to this view, a language is an "ensemble of idiolects ... rather than an entity per se". Linguists study particular languages, such as English or Xhosa, by examining the utterances produced by the people who speak the language.
This contrasts with a view among non-linguists, at least in the United States, that languages as ideal systems exist outside the actual practice of language users: Based on work done in the US, Nancy Niedzielski and Dennis Preston describe a language ideology that appears to be common among American English speakers. According to Niedzielski and Preston, many of their subjects believe that there is one "correct" pattern of grammar and vocabulary that underlies Standard English, and that individual usage comes from this external system.
Linguists who understand particular languages as a composite of unique, individual idiolects must nonetheless account for the fact that members of large speech communities, and even speakers of different dialects of the same language, can understand one another. All human beings seem to produce language in essentially the same way. This has led to searches for universal grammar, as well as attempts to further define the nature of particular languages.
The scope of forensic linguistics includes attempts to identify whether a certain person did or did not produce a given text by comparing the style of the text with the idiolect of the individual. The forensic linguist may conclude that the text is consistent with the individual, rule out the individual as the author, or deem the comparison inconclusive.
In 1995 Max Appedole relied in part on an analysis of Rafael Sebastián Guillén Vicente's writing style to identify him as Subcomandante Marcos, a leader of the Zapatista movement. Though the Mexican government regarded Subcomandante Marcos as a dangerous guerilla, Appedole convinced them that Guillén was a pacifist. These events are credited as an early success of forensic linguistics in criminal profiling in law enforcement.
In 1998 Ted Kaczynski was convicted of a series of bombings known as the "Unabomber" case. The FBI and Attorney General Janet Reno pushed for the publication of a Kaczynski's essay, which led to a tip-off from Kaczynski's brother, who recognized the writing style, his idiolect.
- Zuckermann, Ghil'ad (2006), "A New Vision for 'Israeli Hebrew': Theoretical and Practical Implications of Analysing Israel's Main Language as a Semi-Engineered Semito-European Hybrid Language." Journal of Modern Jewish Studies 5 (1):57–71
- Niedzielski, Nancy & Dennis Preston (2000) Folk Linguistics. Berlin: Mouton de Gruyter.
- Gleitman, Lila (1993) "A human universal: the capacity to learn a language." Modern Philology 90:S13-S33.
- McMenamin, Gerald R. & Dongdoo Choi (2002) Forensic Linguistics: Advances in Forensic Stylistics. London: CRC Press.
- "Marcos, en la mira de Zedillo - Proceso" (in Spanish). 5 August 2002.
- "Maestros y condiscípulos de Tampico recuerdan a Rafael Guillén" (in Spanish).
- Crain, Caleb (1998). "The Bard's fingerprints". Lingua Franca: 29–39.