Complementary distribution
linguistic phenomenon where some phonemes of a language are found in some cases and others are found in similar but different cases; often indicating sound change and divergent mutual descents
In linguistics, complementary distribution (as distinct from contrastive distribution and free variation) is the relationship between two different elements of the same kind in which one element is found in one set of environments and the other element is found in a non-intersecting (complementary) set of environments.
The term often indicates that two superficially-different elements are the same linguistic unit at a deeper level, though more than two elements can be in complementary distribution with one another.
In phonology
Complementary distribution is the distribution of phones in their respective phonetic environments in which one phone never appears in the same phonetic context as the other. When two variants are in complementary distribution, one can predict when each will occur because one can simply look at the environment in which the allophone is occurring.
Complementary distribution is commonly applied to phonology in which similar phones in complementary distribution are usually allophones of the same phoneme. For instance, in English, [p] and [pʰ] are allophones of the phoneme /p/ because they occur in complementary distribution. [pʰ] always occurs when it is the syllable onset and, most likely, when followed by a stressed vowel (as in the word pin). [p] occurs in all other situations (as in the word spin, or in sipping').
There are cases of elements being in complementary distribution but not being considered allophones. For example, English [h] and [ŋ] are in complementary distribution: [h] occurs only at the beginning of a syllable and [ŋ] only at the end.
Begin with the source’s own compact description: “Complementary distribution” is linguistic phenomenon where some phonemes of a language are found in some cases and others are found in similar but different cases; often indicating sound change and divergent mutual descents. The dossier treats that line as a proposition to test through Complementary, distribution and linguistic, not as a finished interpretation.
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This entry incorporates text from “Complementary distribution” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.