In linguistics, vowel length is the perceived duration of a vowel sound. Often the chroneme, or the "longness", acts like a consonant, and may etymologically be one, such as in Australian English. While not distinctive in most dialects of English, vowel length is an important phonemic factor in many other languages, for instance inFinnish,Fijian,Japanese,Old English,andVietnamese. It plays a phonetic role in the majority of dialects of English English, and is said to be phonemic in a few other dialects, such as Australian English and New Zealand English. It also plays a lesser phonetic role in Cantonese, which is exceptional among the spoken variants of Chinese.
Many languages do not distinguish vowel length, and those that do usually distinguish between short vowels and long vowels. There are very few languages that distinguish three vowel lengths, for instance Luiseño. Some languages, such as Finnish, Estonian and Japanese, also have words where long vowels are immediately followed by more vowels, e.g. Japanese hōō "phoenix" or Estonian jäääär "ice edge".
Stress is often reinforced by allophonic vowel length, especially when it is lexical. For example, French long vowels always occur on stressed syllables. Finnish, a language with two phonemic lengths, indicates the stress by adding allophonic length. This gives four distinctive lengths and five physical lengths: short and long stressed vowels, short and long unstressed vowels, and a half-long vowel, which is a short vowel found in a syllable immediately preceded by a stressed short vowel, e.g. i-so.
Among the languages that have distinctive vowel length, there are some where it may only occur in stressed syllables, e.g. in the Alemannic German dialect and Egyptian Arabic. In languages such as Czech, Finnish or Classical Latin, vowel length is distinctive in unstressed syllables as well.
In some languages, vowel length is sometimes better analyzed as a sequence of two identical vowels. In Finnic languages, such as Finnish, the simplest example follows from consonant gradation: haka → haan. In some cases, it is caused by a following chroneme, which is etymologically a consonant, e.g. jää " ← Proto-Uralic *jäŋe. In noninitial syllables, it is ambiguous if long vowels are vowel clusters — poems written in the Kalevala meter often syllabicate between the vowels, and an (etymologically original) intervocalic -h- is seen in this and some modern dialects (e.g. taivaan vs. taivahan "of the sky"). Morphological treatment of diphthongs is essentially similar to long vowels. Interestingly, some old Finnish long vowels have developed into diphthongs, but successive layers of borrowing have introduced the same long vowels again, such that the diphthong and the long vowel again contrast (e.g. nuotti "musical note" vs. nootti "diplomatic note").
In Japanese, most long vowels are the results of the phonetic change of diphthongs; au and ou became ō, iu became yū, eu became yō, and now ei is becoming ē. The change also occurred after the loss of intervocalic phoneme /h/. For example, modern kyōto (Kyoto) exhibits the following changes: kyauto → kyoːto. Another example is shōnen (boy): seunen → syoːnen (shoːnen).
Long vowels may or may not be separate phonemes. In Latin and Hungarian, long vowels are separate phonemes from short vowels, thus doubling the number of vowel phonemes.
Japanese long vowels are analyzed as either two same vowels or a vowel + the pseudo-phoneme, and the number of vowels is five.
Estonian has three distinctive lengths, but the third is suprasegmental, as it has developed from the allophonic variation caused by now-deleted grammatical markers. For example, half-long 'aa' in saada comes from the agglutination *saata+ka "send+(imperative)", and the overlong 'aa' in saada comes from *saa+ta "get+(infinitive)". One of the very few languages to have three lengths, independent of vowel quality or syllable structure, is Mixe. An example from Mixe is "guava", "spider", "knot". Similar claims have been made for Yavapai and Wichita.
Four-way distinctions have been claimed, but these are actually long-short distinctions on adjacent syllables. For example, in kiKamba, there is,,, "hit", "dry", "bite", "we have chosen for everyone and are still choosing".
Vowel length (i.e., "long" and "short"), when applied to English, has several different related meanings.
Traditionally, the vowels (as in bait beet bite boat beauty) are said to be the "long" counterparts of the vowels (as in bat bet bit bot but) which are said to be "short". This terminology reflects their pronunciation before the Great Vowel Shift.
Traditional English phonics teaching, at the preschool to first grade level, often used the term "long vowel" for any pronunciation that might result from the addition of a silent E (e.g., like) or other vowel letter as follows:
|A a||"mat" / "mate"|
|E e||"pet" / "Pete"|
|I i||"twin" / "twine"|
|O o||"not" / "note"|
|U u||"cub" / "cube"|
A mnemonic was that each vowel's long sound was its name.
In Middle English, the long vowels were generally written i..e, e..e, ea, a..e, o..e, oo, u..e. With the Great Vowel Shift, they came to be pronounced . Because ea and oo are digraphs, they are not called long vowels today. Under French influence, the letter u was replaced with ou (or final ow), so it is no longer considered a long vowel either. Thus the so-called "long vowels" of Modern English are those vowels written with the help of a silent e.
In certain dialects of the modern English language, for instance British Received Pronunciation and, to some extent, General American, there is allophonic vowel length: vowel phonemes are realized as longer vowel allophones before voiced consonant phonemes in the coda of a syllable. For example, the vowel phoneme in ‘bat’ is realized as a short allophone in, because the phoneme is unvoiced, while the same vowel phoneme in ‘bad’ is realized as a slightly long allophone (which could be transcribed as), because is voiced. (Incidentally, the final consonant allophones in these syllables also have different relative lengths; the of bat is longer than the of bad.)
Symbolic representation of the two allophonic rules:
In addition, the vowels of Received Pronunciation are commonly divided into short and long, as obvious from their transcription. The short vowels are (as in kit), (as in foot), (as in dress), (as in strut), (as in trap), (as in lot), and (as in the first syllable of ago and in the second of sofa). The long vowels are (as in fleece), (as in goose), (as in nurse), as in north and thought, and (as in father and start). While a different degree of length is indeed present, there are also differences in the quality (lax vs tense) of these vowels, and the currently prevalent view tends to emphasise the latter rather than the former.
|bid||vs||as in beard|
|can meaning able to||vs||as in tin can|
In American English vowel length is phonemic before the alveolar flap, in minimal pairs such as ladder/latter and liter/leader.
The long vowel may often be traced to assimilation. In Australian English, the second element of a diphthong has assimilated to the preceding vowel, giving the pronunciation of bared as, creating a contrast with bed . Another etymology is the vocalization of a fricative such as the voiced velar fricative or voiced palatal fricative, e.g. Finnish illative case, or even an approximant, as the English 'r'.
Estonian, of Finnic languages, exhibits a rare phenomenon, where allophonic length variation becomes phonemic following the deletion of the suffixes causing the allophony. Estonian already distinguishes two vowel lengths, but a third one has been introduced by this phenomenon. For example, the Finnic imperative marker *-k caused the preceding vowels to be articulated shorter, and following the deletion of the marker, the allophonic length became phonemic, as shown in the example below. Similarly, the Australian English phoneme was created by the incomplete application of a rule extending before certain voiced consonants, a phenomenon known as the bad–lad split.
Many long vowels in the Indo-European languages were formed from short vowels and one of the laryngeal sounds, conventionally written h1, h2 and h3. If a laryngeal followed a vowel in Proto-Indo-European, it was usually lost in its later descendants and the preceding vowel became long. However, Proto-Indo-European itself already possessed long vowels as well, usually as the result of older sound changes such as Szemerényi's law and Stang's law.
In the International Phonetic Alphabet the sign (not a colon, but two triangles facing each other in an hourglass shape; Unicode) is used for both vowel and consonant length. This may be doubled for an extra-long sound, or the top half used to indicate a sound is "half long". A breve is used to mark a short vowel or consonant.
Estonian has a three-way phonemic contrast:
saada "to get"
Although not phonemic, the distinction can also be illustrated in certain accents of English:
Consistent use: byta 'to change' vs bytta 'tub' and koma 'coma' vs komma 'to come'
Inconsistent use: fält 'a field' and kam 'a comb' (but the verb 'to comb' is kamma)
Some languages make no distinction in writing. This is particularly the case with ancient languages such as Latin and Old English. Modern edited texts often use macrons with long vowels, however. Australian English does not distinguish the vowels from in spelling, with words like ‘span’ or ‘can’ having different pronunciations depending on meaning.
In non-Latin writing systems, a variety of mechanisms have also evolved.