Length (phonetics)

Long
◌ː
IPA number	503
Encoding
Entity (decimal)	ː
Unicode (hex)	U+02D0

Half long
◌ˑ
IPA number	504
Encoding
Entity (decimal)	ˑ
Unicode (hex)	U+02D1

Extra long
◌ːː

In phonetics, length or quantity is a feature of sounds that have distinctively extended duration compared with other sounds. There are long vowels as well as long consonants (the latter are often called geminates).

Many languages do not have distinctive length. Among the languages that have distinctive length, there are only a few that have both distinctive vowel length and distinctive consonant length. It is more common that there is only one or that they depend on each other.

The languages that distinguish between different lengths have usually long and short sounds. According to some linguists, Estonian and some Sami languages have three phonemic (meaning-distinguishing) lengths for consonants and vowels. Some Low German/Low Saxon varieties in the vicinity of Hamburg and some Moselle Franconian and Ripuiarian Franconian varieties do, too.

Strictly speaking, a pair of a long sound and a short sound should be identical except for their length. In certain languages, however, there are pairs of phonemes that are traditionally considered to be long-short pairs even though they differ not only in length, but also in quality, for instance English "long e" which is /iː/ (as in feet /fiːt/) vs. "short i" which is /ɪ/ (as in fit /fɪt/) or German "long e" which is /eː/ (as in Beet /beːt/ 'garden bed') vs. "short e" which is /ɛ/ (as in Bett /bɛt/ 'sleeping bed'). Also, tonal contour may reinforce the length, as in Estonian, where the over-long length is concomitant with a tonal variation resembling tonal stress marking.

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Wikipedia