In historical linguistics, phonological change is any sound change that alters the distribution of phonemes in a language. In other words, a language develops a new system of oppositions among its phonemes. Old contrasts may disappear, new ones may emerge, or they may simply be rearranged. Sound change may be an impetus for changes in the phonological structures of a language (and likewise, phonological change may sway the process of sound change). One process of phonological change is rephonemicization, in which the distribution of phonemes changes by either addition of new phonemes or a reorganization of existing phonemes. Mergers and splits are types of rephonemicization and are discussed further below.
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Phonemic split in the context of Arabic phonology
While many languages have numerous dialects that differ in phonology, contemporary spoken Arabic is more properly described as a continuum of varieties. This article deals primarily with Modern Standard Arabic (MSA), which is the standard variety shared by educated speakers throughout Arabic-speaking regions. MSA is used in writing in formal print media and orally in newscasts, speeches and formal declarations of numerous types.
Modern Standard Arabic has 28 consonant phonemes and 6 vowel phonemes, with four "emphatic" (pharyngealized) consonants that contrast with their non-emphatic counterparts. Some of these phonemes have coalesced in the various modern dialects, while new phonemes have been introduced through borrowing or phonemic splits. A "phonemic quality of length" applies to consonants as well as vowels.
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