Debuccalization or deoralization is a sound change or alternation in which an oral consonant loses its original place of articulation and moves it to the glottis (,, or ). The pronunciation of a consonant as is sometimes called aspiration, but in phonetics, aspiration is the burst of air accompanying a stop. The word comes from Latin bucca, meaning "cheek" or "mouth". Debuccalization is usually seen as a subtype of lenition, which is often defined as a sound change involving the weakening of a consonant by progressive shifts in pronunciation. As with other forms of lenition, debuccalization may be synchronic or diachronic (i.e. it may involve alternations within a language depending on context or sound changes across time). Debuccalization processes occur in many different types of environments such as the following:

Glottal stop

Arabic

is debuccalized to in several Arabic varieties, such as northern Egyptian, Lebanese, western Syrian, and urban Palestinian dialects, partially also in Jordanian Arabic (especially by female speakers). The Maltese language, which was originally an Arabic dialect, also shows this feature.

Indo-European languages

British and American English

Most English-speakers in England and many speakers of American English debuccalize to a glottal stop in two environments: in word-final position before another consonant (American English IPA) Before a syllabic following, , , a vowel, or a diphthong. The may then also be nasally released. (American English IPA)

Cockney English

In Cockney English, is often realized as a glottal stop between vowels, liquids, and nasals (notably in the word bottle), a process called t-glottalization.

German

The German ending -en is commonly realized as an assimilated syllabic nasal. Preceding voiceless stops are then glottally released: Latten ('laths'), Nacken ('nape of the neck'). When such a stop is additionally preceded by a homorganic sonorant, it tends to be debuccalized entirely and create the clusters. For example, Lumpen ('rag'), Banken ('banks'). Voiced stops are not usually debuccalized. However, many Upper German and East Central German dialects merge voiced and unvoiced stops at least word-internally, and the merged consonants may be debuccalized. For example, in Bavarian, both Anten ('ducks') and Anden ('Andes') are pronounced. Speakers are often unaware of that. However, Standard German spoken in Luxembourg often lacks syllabic sonorants under the influence of Luxembourgish, so that -en is pronounced, rather than or.

Austronesian languages

Indonesian and Malay

In both languages, syllable-final -k is either realized as or.

Sulawesi languages

Debuccalization is very common in parts of Sulawesi. Especially in the South Sulawesi branch, most languages have turned word-final *t and *k into a glottal stop. In every Gorontalic language except Buol and Kaidipang, *k was replaced by a glottal stop, and lost altogether in word-initial position: *kayu → Gorontalo ayu wood, *konuku → olu'u fingernail. However, if it followed *ŋ, then *k voiced into g in Gorontalo (*koŋkomo → onggomo handful). Debuccalization is also common in the Sangiric branch. In Sangir and Bantik, all final voiceless stops were reduced into ʔ (*manuk → manu ' "bird"). Also in Ratahan, final *t became ʔ (*takut → taku ' "to fear"). In Talaud, all instances of Proto-Sangiric *k were debuccalized into ʔ except when following *ŋ (*kiki → i'i "to bite", but *beŋkol → bengkola "bent"). Other newer instances of k resulted from *R when geminated or being word-final (ʐ elsewhere), e.g. *bəRu → bakku "new", *bibiR → biwikka "lip", *bəŋaR → bangngaka "molar".

Polynesian languages

Many Polynesian languages lost the original glottal stop *ʔ of their ancestor Proto-Polynesian, but then debuccalized other consonants into a glottal stop. This applied to different consonants depending on the language, for example:

Glottal fricative

Indo-European languages

Slavic

Older was spirantized and later debuccalized in languages such as Belarusian, the Czech–Slovak languages, Ukrainian, and Upper Sorbian, e.g. Serbian bog, Russian box, Czech bůh, Ukrainian bih.

English

Scots and Scottish English

In some varieties of Scots and Scottish English, particularly on the West Coast, a non word-final th shifted to, a process called th-debuccalization. For example, is realized as.

Scouse

Pre-pausally, may be debuccalized to [h], eg. it, lot, that, what pronounced.

Proto-Greek

In Proto-Greek, shifted to initially and between sonorants (vowels, liquids, and nasals). Intervocalic had been lost by the time of Ancient Greek, and vowels in hiatus were contracted in the Attic dialect. Before a liquid or nasal, an was assimilated to the preceding vowel in Attic-Ionic and Doric and to the following nasal in Aeolic. The process is also described as the loss of and the subsequent lengthening of a vowel or consonant, which kept the syllable the same length (compensatory lengthening).

Sanskrit

In Sanskrit, becomes (written ḥ in transliteration) before a pause: e.g. kā́mas ('erotic love') becomes kā́maḥ. Additionally, the Proto-Indo-European aspirated voiced palato-velar *ǵʰ became through successive affrication, assibilation and debuccalization: e.g. *bʰeh₂ǵʰús "arm" becomes Sanskrit bāhúḥ.

Bengali

In many Eastern Bengali dialects, the voiceless palato-alveolar sibilant can become debuccalized to glottal or, e.g. "wife's brother" is , and "sea" is. The tenuis and aspirated forms of the labial stop and velar stop can get lenited to and respectively, but also be further debuccalized to or, e.g. "mad" is and "beggar, faqir" is. In some cases, even the glottal fricative is dropped, e.g. "(he / she / it) came" is.

West Iberian

Spanish

A number of Spanish dialects debuccalize to or at the end of a syllable or intervocalically in certain instances.

Galician

In many varieties of Galician, as well as in Galician-influenced Spanish, the phoneme may debuccalize (gheada) to in most or all instances; and are also possible realizations. There is also an inverse hypercorrection process of older or less educated Galician speakers replacing the phoneme of the Spanish language with, which is called gueada.

Portuguese

Portuguese is much less affected by debuccalization, but it is especially notable in its Brazilian variety. Throughout Brazil, the phoneme (historically an alveolar trill that moved to an uvular position) has a rather long inventory of allophones:. Only is uncommon. Few dialects, such as sulista and fluminense, give preference to voiced allophones; elsewhere, they are common only as coda, before voiced consonants. In such dialects, especially among people speaking an educated variety of Portuguese, it is usual for the rhotic coda in the syllable rhyme to be an alveolar tap, as in European Portuguese and many registers of Spanish, or to be realized as or. In the rest of the country, it is generally realized as, even by speakers who either do not normally use that allophone or delete it entirely, as is common in the vernacular. However, in some mineiro- and mineiro-influenced fluminense rural registers, is used but as an allophone of (rhotic consonants are most often deleted), a mar-mal merger, instead of the much more common and less-stigmatized mau-mal merger characteristic of all Brazilian urban centers except for those bordering Mercosur countries, where coda was preserved, and the entire North and Northeast regions. Its origin is the replacement of indigenous languages and línguas gerais by Portuguese, which created, and r-colored vowel as allophones of both (now mostly ) and (now mostly ) phonemes in the coda since Native Brazilians could not easily pronounce them (caipira dialect). The later Portuguese influence from other regions made those allophones become rarer in some areas, but the mar-mal merger remained in a few isolated villages and towns. Finally, many fluminense registers, especially those of the poor and of the youth, most northern and northeastern dialects, and, to a much minor degree, all other Brazilian dialects, debuccalize (that is, ) but less so than in Spanish. However, a mar-mas merger or even a mar-mais merger occurs: mas mesmo assim "but even so" or mas mesma, sim "though, right, the same (f) one" ; mais light "lighter, more slim", or also "less caloric/fatty" ; mas de mim, não "but from me, no" or mais de mim, não "not more from me". A coda rhotic in the Brazilian dialects in the Centro-Sul area is hardly ever glottal, and the debuccalized is unlikely to be confused with it.

Romanian

In the Moldavian dialect of Romanian, is debuccalized to and so, for example, să fie becomes să hie. The same occurred in Old Spanish, Old Gascon, and Old Japanese and still occurs in Sylheti.

Goidelic languages

In Scottish and Irish Gaelic, s and t changed by lenition to, spelled sh and th.

Faliscan

Inscription in Faliscan from the 4th century BC on show occasional debuccalization of to (e.g. hileo : Latin filius). Whether the shift is displayed in the inscriptions is highly irregular, with some forms even showing an ostensibly opposite shift of written f in place of an expected h (e.g. fe : Latin hic), possibly by means of hypercorrection.

Austronesian languages

Malay

In several Malay dialects in the peninsular, final -s is realized as.

Batak languages

In the Batak branch, all southern languages (but not the northern ones including Karo), have debuccalized *k into h, except when word-final or followed *ŋ. Both Angkola and Mandailing have restored k within the sequence hVhV (Angkola kehe, Mandailing ke, but Toba hehe), or when following a consonant in Mandailing (ala "scorpion" → parkalahan). Mandailing, however has also further deleted *h (*kalak → alak "person"), except in the sequence -aha- (dahan "mushroom", not *dan).

Polynesian languages

Polynesian languages commonly reflect debuccalization not only into a glottal stop, but also into a glottal fricative. The exact distribution depends on the language:

Other families

Yoruboid languages

Debuccalization occurs extensively within the dialectal continuum of Yoruboid languages, particularly among the Olukumi language, Igala language, the Northeast Yoruba dialect known as Owe, and Southeastern dialects of the Yoruba language, such as Ikale. Many of these shifts came from Proto-Yoruboid language (or its descendant language, Proto-Edekiri), and descendant languages shifted from to. In other cases shifts from to also occur from Proto-Yoruboid to Standard Yoruba. Many other alternatives shift from to, but it is unclear if that process is associated with the debuccalization occurring. Debuccalization also occurs in other Volta-Niger languages, including Igbo, the Ayere-Ahan languages, and the Edo.

Kannada

In old Kannada at around 10th-14th century, most of the initial debuccalized into a e.g. OlKn. pattu, MdKn. hattu "ten".

Slavey

All coda consonants in Slavey must be glottal. When a non-glottal consonant would otherwise be positioned in a syllable coda, it debuccalizes to :

Loanwords

Debuccalization can be a feature of loanword phonology. For example, debuccalization can be seen in Indonesian loanwords into Selayar.