Definition of "dialect"

dialect

/ˈdaɪ.əˌlɛkt/

noun
plural dialects
1. (linguistics, strict sense) A lect (often a regional or minority language) as part of a group or family of languages, especially if they are viewed as a single language, or if contrasted with a standardized idiom that is considered the 'true' form of the language (for example, Cantonese as contrasted with Mandarin Chinese or Bavarian as contrasted with Standard German).
  Quotations
  The question could be put: 'Is there anything inherent in a dialect which gives it a negative stigma or is it that the status of the majority of the speakers is transferred to the dialect?' — something that occurs in many regions in different countries.
  1995, Michael [G.] Clyne, The German language in a changing Europe, Cambridge University Press, page 117
  Bloomfield, for example, noted that “local dialects are spoken by the peasants and the poorest people of the towns” (1933: 50) though he also thought that the lower middle class spoke 'sub-standard' speech.
  2010, Mirjam Fried, Jan-Ola Östman, Jef Verschueren, editors, Variation and Change: Pragmatic perspectives (Handbook of Pragmatics Highlights; 6), John Benjamins Publishing Company, Dialect, by Ronald Macaulay, page 61
  Among common errors still persisting in the minds of educated people, one error which dies very hard is the theory that a dialect is an arbitrary distortion of the mother tongue, a wilful mispronunciation of the sounds, and disregard of the syntax of a standard language.
  2014, Elizabeth Mary Wright (died 1958), Rustic Speech and Folk-Lore
2. (linguistics, broad sense) A variety of a language that is characteristic of a particular area, community, or social group, differing from other varieties of the same language in relatively minor ways as regards grammar, phonology, and lexicon.
  Quotations
  And in addition, many dialects of English make no morphological distinction between Adjectives and Adverbs, and thus use Adjectives in contexts where the standard language requires -ly Adverbs
  1988, Andrew Radford, Transformational Grammar: A First Course, Cambridge, UK: Cambridge University Press, page 139
3. (derogatory) Language that is perceived as substandard or wrong.
  Quotations
  Well, those children don't speak dialect, not in this school. Maybe in the public schools, but not here.
  1975, H. Carl, Linguistic Perspectives on Black English, page 219
  […] on the second day, Miss Anderson gave the school a lecture on why it was wrong to speak dialect. She had ended by saying "Respectable people don't speak dialect."
  1994, H. Nigel Thomas, Spirits in the Dark, Heinemann, page 11
  Many even deny it and say something like this: "No, we don't speak a dialect around here.
  1967, Roger W. Shuy, Discovering American Dialects, National Council of Teachers of English, page 1
4. (colloquial, offensive) A language existing only in an oral or non-standardized form, especially a language spoken in a developing country or an isolated region.
5. (computing, programming) A variant of a non-standardized programming language.
6. (ornithology) A variant form of the vocalizations of a bird species restricted to a certain area or population.
  Quotations
  A curious question, which has as yet attracted but little attention, is whether the notes of the same species of Bird are in all countries alike. From my own observation I am inclined to think that they are not, and that there exist "dialects," so to speak, of the song.
  1896, Alfred Newton, A Dictionary of Birds, page 893