Implosive consonant

Implosive consonants are stops (and possibly affricates) with a mixed glottalic ingressive and pulmonic egressive airstream mechanism.^[1] That is, the airstream is controlled by moving the glottis downward in addition to expelling air from the lungs. Therefore, unlike the purely glottalic ejective consonants, implosives can be modified by phonation. Contrastive implosives are found in approximately 13%^[2] of the world's languages.

In the International Phonetic Alphabet, implosives are indicated by modifying the top of a letter (voiced stop) with a downward-facing hook: ⟨ɓ ɗ ʄ ɠ ʛ ⟩.

Articulation

During the occlusion of the stop, pulling the glottis downward rarefies the air in the vocal tract. The stop is then released. In languages whose implosives are particularly salient, that may result in air rushing into the mouth before it flows out again with the next vowel. To take in air sharply in that way is to implode a sound.^[3]

However, probably more typically, there is no movement of air at all, which contrasts with the burst of the pulmonary plosives. This is the case with many of the Kru languages, for example. That means that implosives are phonetically sonorants (not obstruents) as the concept of sonorant is usually defined. However, implosives can phonologically pattern as both; that is, they may be phonological sonorants or obstruents depending on the language.

George N. Clements (2002) actually proposes that implosives are phonologically neither obstruents nor sonorants.

The vast majority of implosive consonants are voiced, so the glottis is only partially closed. Because the airflow required for voicing reduces the vacuum being created in the mouth, implosives are easiest to make with a large oral cavity.

Bilabial [ɓ] is thus the easiest implosive to pronounce and so it is the most common one around the world. Velar [ɠ], on the other hand, is quite rare (uvular [ʛ] is even rarer). That is the opposite pattern to the ejective consonant in which it is the velar articulation that is most common and the bilabial articulation that is rare.

Types

IPA chart non-pulmonic consonants
Clicks ʘ ǀ ǃ ǂ ǁ ʘ̃ ʘ̃ˀ ʘ͡q ʘ͡qʼ ‼ Implo­sives ɓ ɗ ʄ ᶑ ɠ ʛ Eject­ives pʼ t̪ʼ tʼ ʈʼ cʼ kʼ qʼ fʼ θʼ sʼ ɬʼ ʃʼ ʂʼ ɕʼ xʼ χʼ tsʼ tɬʼ cʎ̝̥ʼ tʃʼ ʈʂʼ kxʼ kʟ̝̊ʼ qχʼ
This table contains phonetic symbols, which may not display correctly in some browsers. [Help]
IPA help • IPA key •  audio help • chart • view

The attested voiced implosive stops are the following:

• voiced bilabial implosive [ɓ]
• voiced dental implosive [ɗ̪ ]
• voiced alveolar implosive [ɗ ]
• voiced retroflex implosive [ᶑ ] ("letter not explicitly IPA approved")
• voiced palatal implosive [ ʄ ]
• voiced velar implosive [ɠ ]
• voiced labial–velar implosive [ɠɓ]
• voiced uvular implosive [ʛ ]

There are no IPA symbols for implosive fricatives. Implosive fricatives are unknown, and implosive affricates unlikely. A few affricates have been reported (like [ɗʒ] in Roglai and Komo; allophonic [ɗz] and [ɗɮ] in Gitxsan), but more investigation may reanalyze them as something else.^[4]

Voiceless implosives

Consonants variously called "voiceless implosives," "implosives with glottal closure,"^[5] or "reverse ejectives" involve a slightly different airstream mechanism, purely glottalic ingressive.^[1] The glottis is closed so no pulmonic airstream is possible. The IPA once dedicated symbols ⟨ƥ ƭ ƈ ƙ ʠ ⟩ to such sounds, but they were withdrawn in 1993. They are now transcribed ⟨ɓ̥ ɗ̥ ʄ̊ ɠ̊ ʛ̥ ⟩ or occasionally ⟨pʼ↓ tʼ↓ cʼ↓ kʼ↓⟩. Some authors use a superscript left pointer, ⟨p˂ t˂ c˂ k˂⟩, but that is not an IPA symbol and has other uses.

The attested voiceless implosive stops are:

• voiceless bilabial implosive [ɓ̥]
• voiceless alveolar implosive [ɗ̥ ]
• voiceless retroflex implosive [ᶑ̥ ]
• voiceless palatal implosive [ ʄ̥ ]
• voiceless velar implosive [ɠ̊ ] (paraphonemic in English)
• voiceless uvular implosive [ʛ̥ ]
• voiceless labial–velar implosive [ɠ̊ɓ̥] (in Igbo per Floyd 1981)

Other implosives

Nasals have been reported to have implosive releases; however, phonologically, they are sequences such as /N-ɓ/, and phonetically, they may be weakened implosive stops rather than implosive nasals.^[6]

Attested implosive consonants^[7]
(excluding secondary phonations and articulations)

	Bilabial	Linguo­labial	Dental	Alveolar	Labial– alveolar	Retroflex	Palatal	Velar	Labial– velar	Uvular
Stop	ɓ ƥ		ɗ̪ ƭ̪	ɗ ƭ	[8]	ᶑ ƭ̢[9]	ʄ ƈ	ɠ ƙ	ɠ͡ɓ ƙ͜ƥ	ʛ ʠ
Affricate	(theoretical)
Nasal	? m̩^ɓ			? n̩^ɗ

Occurrence

Implosives are widespread among the languages of Sub-Saharan Africa and Southeast Asia and are found in a few languages of the Amazon Basin. They are rarely reported elsewhere but occur in scattered languages such as the Mayan languages in North America, Saraiki and Sindhi in the Indian subcontinent and in Vietnamese. They appear to be entirely absent from Europe and northern Asia and from Australia, even from the Australian ceremonial language Damin, which uses every other possible airstream mechanism.

However, fully voiced stops are often slightly implosive, but it is not always described explicitly if there is no contrast with modal-voiced plosives, as occurs around the world, from Maidu to Thai to many Bantu languages, including Swahili.

Sindhi and Saraiki have an unusually large number of contrastive implosives, with /ɓ ᶑ ʄ ɠ/.^[5][10] Although Sindhi has a dental–retroflex distinction in its plosives, with /b d ɖ ɟ ɡ/, the contrast is neutralized in the implosives. A contrastive retroflex implosive /ᶑ / may, however, occur in Ngad'a, a language spoken in Flores, Indonesia.^[11]

More examples can be found in the articles on individual implosives.

Voiceless implosives are quite rare but are found in languages as varied as the Owere dialect of Igbo in Nigeria (/ƥ/ /ƭ/), Krongo in Sudan, the Uzere dialect of Isoko, the closely related Lendu and Ngiti languages in the Democratic Republic of Congo, Serer in Senegal (/ƥ ƭ ƈ/), and some dialects of the Poqomchi’ and Quiche languages in Guatemala (/ƥ ƭ/). Owere Igbo has a seven-way contrast among bilabial stops, /pʰ p ƥ bʱ b ɓ m/, and its alveolar stops are similar. The dorsal stops [ƙ] [ʠ] do not seem to be attested in the literature as speech sounds,^[12] but /ʠ/ has been claimed for Kaqchikel. Lendu has been claimed to have voiceless /ɓ̥ ɗ̥ ɠ̊/, but they may actually be creaky-voiced implosives.^[5]

Some English speakers use a voiceless velar implosive [ƙ] to imitate the "glug-glug" sound of liquid being poured from a bottle, but others use a voiced implosive [ɠ].^[13]

References

1. Phonetics for communication disorders. Martin J. Ball and Nicole Müller. Routledge, 2005.
2. Maddieson, Ian. 2008. Glottalized Consonants. In: Haspelmath, Martin & Dryer, Matthew S. & Gil, David & Comrie, Bernard (eds.) The World Atlas of Language Structures Online. Munich: Max Planck Digital Library, chapter 7. Available online at http://wals.info/feature/7 Accessed on 2008-03-28.
3. Entry: "Implode" (2. [with obj.] [phonetic terminology]: utter or pronounce (a consonant) with a sharp intake of air.) New Oxford American Dictionary 3rd edition © 2010
4. For example, "Gitksan does not have voiced implosive stops; rather, it has lax glottalized stops that display a creaky voice quality at the margin of the vowel in pretonic (and syllable-final) environments." — Bruce Rigsby & John Ingram (1990) "Obstruent Voicing and Glottalic Obstruents in Gitksan". International Journal of American Linguistics, vol. 56, no. 2, pp. 251–263.
5. Ladefoged, Peter; Maddieson, Ian (1996). The Sounds of the World's Languages. Oxford: Blackwell. ISBN 0-631-19814-8.
7. Bickford & Floyd (2006) Articulatory Phonetics, Table 25.1, augmented by sources at the articles on individual consonants
8. Reported labial–alveolar implosive in Margi turns out to be a consonant sequence
9. Letter not supported by Unicode
10. Swahili has a similar /ɓ ɗ ʄ ɠ/, without contrasting with voiced pulmonic stops, unlike in Sindhi.
11. Djawanai, Stephanus. (1977). A description of the basic phonology of Nga'da and the treatment of borrowings. NUSA linguistic studies in Indonesian and languages in Indonesia, 5, 10-18
12. Phonetic Symbol Guide, Geoffrey K. Pullum, William A. Ladusaw
13. Pike, Phonetics, 1943:40

Bibliography

• Clements, George N.; Sylvester Osu (2002). "Explosives, Implosives, and Nonexplosives: the Linguistic Function of Air Pressure Differences in Stops" (PDF). Laboratory Phonology. 7. Berlin: Mouton de Gruyter. pp. 299–350. Retrieved 2010-01-08.
• Demolin, Didier; Ngonga-Ke-Mbembe, Hubert; & Soquet, Alain. (2002). Phonetic characteristics of an unexploded palatal implosive in Hendo. Journal of the International Phonetic Association, 32, 1-15.
• Ladefoged, Peter; Maddieson, Ian (1996). The Sounds of the World's Languages. Oxford: Blackwell. ISBN 0-631-19814-8.
• Maddieson, Ian. (1984). Patterns of sounds. Cambridge studies in speech science and communication. Cambridge: Cambridge University Press.