phonetics Phonetics is a branch of linguistics that studies how humans produce and perceive sounds or, in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians ...

, an occlusive, sometimes known as a stop, is a

consonant In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract, except for the h sound, which is pronounced without any stricture in the vocal tract. Examples are and pronou ...

sound produced by occluding (i.e. blocking) airflow in the

vocal tract The vocal tract is the cavity in human bodies and in animals where the sound produced at the sound source (larynx in mammals; syrinx in birds) is filtered. In birds, it consists of the trachea, the syrinx, the oral cavity, the upper part of t ...

, but not necessarily in the nasal tract. The duration of the block is the ''occlusion'' of the consonant. An occlusive may refer to one or more of the following, depending on the author: * Stops, or more precisely, oral stops—also known as plosives—are oral occlusives, where the occlusion of the vocal tract stops all airflow—oral and nasal. :Examples in English are ( voiced) , , and ( voiceless) , , . * Nasals, also known as nasal stops, are nasal occlusives, where occlusion of the vocal tract shifts the airflow to the nasal tract. :Examples in English are , , and . * Affricates such as English , are partial occlusives. Typically ''stops'' and ''affricates'' are contrasted, but affricates are also described as ''stops with fricative release'', contrasting with ''simple stops'' (= plosives). * Implosives, in which the airstream differs from typical stops and affricates (no examples in English). * Ejectives, with yet another airstream (no examples in English). * Click consonants, such as the exclamation ''tsk! tsk!'' made when expressing reproach (often humorously) or pity, are double occlusives with yet a fourth airstream mechanism. They may be oral occlusives, nasals, affricates, or ejective. ''Oral occlusive'' may mean any of the above apart from nasal occlusives, but typically means stop/plosive. ''Nasal occlusive'' may be used to distinguish the simple nasal sounds from other

nasal consonant In phonetics, a nasal, also called a nasal occlusive or nasal stop in contrast with an oral stop or nasalized consonant, is an occlusive consonant produced with a lowered velum, allowing air to escape freely through the nose. The vast majo ...

s. The terms 'stop' and 'occlusive' are used inconsistently in the literature. They may be synonyms, or they may distinguish nasality as here. However, some authors use them in the opposite sense to here, with 'stop' being the generic term (''oral stop, nasal stop''), and 'occlusive' being restricted to oral consonants. Ladefoged and Maddieson (1996) prefer to distinguish 'stop' from 'nasal'. They say, :''Note that what we call simply nasals are called nasal stops by some linguists. We avoid this phrase, preferring to reserve the term 'stop' for sounds in which there is a complete interruption of airflow.''

Common occlusives

All languages in the world have occlusives and most have at least the voiceless stops , , and the nasals , and . However, there are exceptions. Colloquial Samoan lacks the coronals and , and several North American languages, such as the northern Iroquoian languages, lack the labials and . In fact, the labial plosive is the least stable of the voiceless stops in the languages of the world, as the unconditioned sound change → (→ → Ø) is quite common in unrelated languages, having occurred in the history of Classical Japanese,

Classical Arabic Classical Arabic or Quranic Arabic () is the standardized literary form of Arabic used from the 7th century and throughout the Middle Ages, most notably in Umayyad Caliphate, Umayyad and Abbasid Caliphate, Abbasid literary texts such as poetry, e ...

and

Proto-Celtic Proto-Celtic, or Common Celtic, is the hypothetical ancestral proto-language of all known Celtic languages, and a descendant of Proto-Indo-European. It is not attested in writing but has been partly Linguistic reconstruction, reconstructed throu ...

, for instance. Some of the Chimakuan, Salishan, and Wakashan languages near Puget Sound lack nasal occlusives and , as does the Rotokas language of

Papua New Guinea Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...

. In some African and South American languages, nasal occlusives occur only in the environment of

nasal vowel A nasal vowel is a vowel that is produced with a lowering of the soft palate (or velum) so that the air flow escapes through the nose and the mouth simultaneously, as in the French vowel /ɑ̃/ () or Amoy []. By contrast, oral vowels are p ...

s and so are allophone, not distinctive. Formal Samoan has nasals and but only one word with velar ; colloquial Samoan conflates these to . Ni‘ihau Hawaiian has for to a greater extent than Standard Hawaiian, but neither distinguishes a from a . It may be more accurate to say that Hawaiian and colloquial Samoan do not distinguish velar and coronal stops than to say they lack one or the other. Yanyuwa distinguishes nasals and plosives in seven places of articulations /m n̪ n ṉ ɳ ŋ̟ ŋ̠/ and /b d̪ d ḏ ɖ ɡ̟ ɡ̠/ (it does not have voiceless plosives) which is the most out of all languages.

References

{{Articulation navbox Occlusive consonants