Phonemic contrast is the property that allows the discrimination of distinctive speech elements of a language and the accompanying ability of a listener to distinguish meaning.
The term "phoneme" itself is defined in terms of contrast: The phoneme can be described as "The smallest contrastive linguistic unit which may bring about a change of meaning". In this context, a pair of close phonemes may also be called a phonemic contrast, to distinguish them from being allophones.
A phonemic feature is called contrastive, if it ensures a phonetic contrast for two otherwise similar phonemes. For example, vowel length may be contrastive in some languages and allophonic in others.
Even within a single language, a feature may or may not ensure contrast. For example, Thai has several sets of stop consonants that differ in terms of voicing (whether or not the vocal cords vibrate) and aspiration (whether a puff of air is released). Yet the language has no voiced velar consonant (/ɡ/). This peculiarity is called a phonological gap or a "hole in the pattern".
|plain voiceless||aspirated voiceless||voiced consonant|
The phonemic contrast of a word may be formally defined in terms of the number of phonemically similar items in the lexicon of a particular language (dialect, variety, etc.), which is a measure of the ease of the recognizability of a word.
Some speech phenomena may lead to the neutralization of phonemic contrasts. For example, due to final-obstruent devoicing, Russian бес ('demon', phonemically /bʲes/) and без ('without', phonemically /bʲez/) are pronounced identically in isolation as [bʲɛs].
- Giegerich, H.J. (1992). English Phonology: An Introduction. Cambridge University Press. p. 250. ISBN 9780521336031. Retrieved 2015-02-11.
- Gimson 2008, p. 41.
- Abramson, Arthur S. (1962). The Vowels and Tones of Standard Thai: Acoustical Measurements and Experiments. Bloomington: Indiana University Research Center in Anthropology, Folklore, and Linguistics.
- Luce and Pisoni 1998 as cited in "Effective contrast and alternation", Andrew Wedel (University of Arizona)
- David W. Crabb, Ekoid Bantu Languages of Ogoja, Eastern Nigeria, Part 1, Introduction, Phonology and Comparative Vocabulary, 2011, ISBN 0521175275, p. 19