Editing Gemination (section)

==Phonology==
Gemination of consonants is distinctive in some languages and then is subject to various phonological constraints that depend on the language.

In some languages, like Italian, Swedish, [[Faroese language|Faroese]], [[Icelandic language|Icelandic]], and [[Luganda]], consonant length and vowel length depend on each other. A short vowel within a stressed syllable almost always precedes a long consonant or a consonant cluster, and a long vowel must be followed by a short consonant. In [[Classical Arabic]], a [[long vowel]] was lengthened even more before permanently-geminate [[consonant]]s.

In other languages, such as [[Finnish language|Finnish]], consonant length and vowel length are independent of each other. In Finnish, both are phonemic; {{lang|fi|taka}} {{IPA|/taka/}} 'back', {{lang|fi|takka}} {{IPA|/takːa/}} 'fireplace' and {{lang|fi|taakka}} {{IPA|/taːkːa/}} 'burden' are different, unrelated words. Finnish consonant length is also affected by [[consonant gradation]]. Another important phenomenon is [[sandhi]], which produces long consonants at word boundaries when there is an [[phoneme#Neutralization and archiphonemes|archiphonemic]] [[glottal stop]] {{IPA|{{!}}otaʔ se{{!}}}} > {{lang|fi|otas se}} 'take it ([[Imperative mood|imperative]])!'.

In addition, in some Finnish compound words, if the initial word ends in an {{lang|fi|e}}, the initial consonant of the following word is geminated: {{lang|fi|jätesäkki}} 'trash bag' {{IPA|[jætesːækːi]}}, {{lang|fi|tervetuloa}} 'welcome' {{IPA|[terʋetːuloa]}}. In certain cases, a {{lang|fi|v}} after a {{lang|fi|u}} is geminated by most people: {{lang|fi|ruuvi}} 'screw' {{IPA|/ruːʋːi/}}, {{lang|fi|vauva}} 'baby' {{IPA|[ʋauʋːa]}}. In the [[Tampere]] dialect, if a word receives gemination of {{lang|fi|v}} after {{lang|fi|u}}, the {{lang|fi|u}} is often deleted ({{lang|fi|ruuvi}} {{IPA|[ruʋːi]}}, {{lang|fi|vauva}} {{IPA|[ʋaʋːa]}}), and {{lang|fi|lauantai}} 'Saturday', for example, receives a medial {{lang|fi|v}} {{IPA|[lauʋantai]}}, which can in turn lead to deletion of {{lang|fi|u}} ({{IPA|[laʋːantai]}}).

Distinctive consonant length is usually restricted to certain consonants and environments. There are very few languages that have initial consonant length; among those that do are [[Pattani Malay language|Pattani Malay]], [[Chuukese language|Chuukese]], [[Moroccan Arabic]], a few [[Romance languages]] such as [[Sicilian language|Sicilian]] and [[Neapolitan language|Neapolitan]], as well as many [[High Alemannic German]] dialects, such as that of [[Thurgovia]]. Some African languages, such as [[Setswana]] and [[Luganda]], also have initial consonant length: it is very common in Luganda and indicates certain [[grammar|grammatical]] features. In [[colloquial Finnish]] and [[Italian phonology|Italian]], long consonants occur in specific instances as sandhi phenomena.

The difference between singleton and geminate consonants varies within and across languages. [[Sonorant]]s show more distinct geminate-to-singleton ratios while [[sibilant]]s have less distinct ratios. The [[Bilabial consonant|bilabial]] and [[Alveolar consonant|alveolar]] geminates are generally longer than [[Velar consonant|velar]] ones.<ref name="Khattab2014" />

The reverse of gemination reduces a long consonant to a short one, which is called ''degemination''. It is a pattern in Baltic-Finnic [[consonant gradation]] that the strong grade (often the [[nominative]]) form of the word is degeminated into a weak grade (often all the other cases) form of the word: {{lang|fi|taakka}} > {{lang|fi|taakan}} (burden, of the burden). As a historical restructuring at the [[Phoneme|phonemic level]], word-internal long consonants degeminated in [[Western Romance]] languages: e.g. Spanish /ˈboka/ 'mouth' vs. Italian /ˈbokka/, both of which evolved from Latin /ˈbukka/.<ref>{{Cite web|url=https://archive.org/details/romanischesetymo00meyeuoft/page/99/mode/1up?q=bucca|title = Romanisches etymologisches Wörterbuch|year = 1911}}</ref>