Stop (consonant)

In phonetics, a plosive, also known as an occlusive or simply a stop, is a pulmonic consonant in which the vocal tract is blocked so that all airflow ceases.

The occlusion may be made with the tongue tip or blade (, ), tongue body (, ), lips (, ), or glottis (). Plosives contrast with nasals, where the vocal tract is blocked but airflow continues through the nose, as in and , and with fricatives, where partial occlusion impedes but does not block airflow in the vocal tract.

Terminology

The terms ''stop, occlusive,'' and ''plosive'' are often used interchangeably. Linguists who distinguish them may not agree on the distinction being made. The terms refer to different features of the consonant. "Stop" refers to the airflow that is stopped. "Occlusive" refers to the articulation, which occludes (blocks) the vocal tract. "Plosive" refers to the release burst (plosion) of the consonant. Some object to the use of "plosive" for inaudibly released stops, which may then instead be called "applosives". The International Phonetic Association and the International Clinical Phonetics and Linguistics Association use the term "plosive".

Either "occlusive" or "stop" may be used as a general term covering the other together with nasals. That is, 'occlusive' may be defined as oral occlusive (plosives and affricates) plus nasal occlusives (nasals such as , ), or 'stop' may be defined as oral stops (plosives) plus nasal stops (nasals). Ladefoged and Maddieson (1996) prefer to restrict 'stop' to oral non-affricated occlusives. They say,
:''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.''

In addition, they restrict "plosive" for a pulmonic consonants; "stops" in their usage include ejective and implosive consonants.

If a term such as "plosive" is used for oral non-affricated obstruents, and nasals are not called nasal stops, then a ''stop'' may mean the glottal stop; "plosive" may even mean non-glottal stop. In other cases, however, it may be the word "plosive" that is restricted to the glottal stop. Generally speaking, plosives do not have plosion (a release burst). In English, for example, there are plosives with no audible release, such as the in ''apt''. However, English plosives do have plosion in other environments.

In Ancient Greek, the term for plosive was (''áphōnon''), which means "unpronounceable", "voiceless", or "silent", because plosives could not be pronounced without a vowel. This term was calqued into Latin as , and from there borrowed into English as ''mute''. ''Mute'' was sometimes used instead for voiceless consonants, whether plosives or fricatives, a usage that was later replaced with ''surd'', from Latin "deaf" or "silent", a term still occasionally seen in the literature. For more information on the Ancient Greek terms, see .

Articulation

A plosive is typically analysed as having up to three phases:
*Approach, during which articulators come together
*Hold (or "occlusion" or "closure"), during which the articulators are held and block the airstream
*Release (or "burst" or "plosion"), when the articulators are separated, releasing the compressed air

Only the hold phase is requisite. A plosive may lack an approach when it is preceded by a consonant that involves an occlusion at the same place of articulation, as in in ''end'' or ''old''. In many languages, such as Malay and Vietnamese, word-final plosives lack a release burst, even when followed by a vowel, or have a nasal release. See no audible release.

Nasal occlusives are somewhat similar. In the catch and hold, airflow continues through the nose; in the release, there is no burst, and final nasals are typically unreleased across most languages.

In affricates, the catch and hold are those of a plosive, but the release is that of a fricative. That is, affricates are plosive–fricative contours.

Common plosives

All spoken natural languages in the world have plosives, and most have at least the voiceless plosives , , and . However, there are exceptions: Colloquial Samoan lacks the coronal , and several North American languages, such as the northern Iroquoian and southern Iroquoian languages (i.e., Cherokee), and Arabic lack the labial . In fact, the labial is the least stable of the voiceless plosives 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, and Proto-Celtic, for instance. Formal Samoan has only one word with velar ; colloquial Samoan conflates and to . Ni‘ihau Hawaiian has for to a greater extent than Standard Hawaiian, but neither distinguish a from a . It may be more accurate to say that Hawaiian and colloquial Samoan do not distinguish velar and coronal plosives than to say they lack one or the other. Ontena Gadsup has only 1 phonemic plosive /ʔ/. Yanyuwa distinguishes plosives in 7 places of articulations /b d̪ d ḏ ɖ ɡ̟ ɡ̠/ (it does not have voiceless plosives) which is the most out of all languages.

See Common occlusives for the distribution of both plosives and nasals.

Classification

Voice

Voiced plosives are pronounced with vibration of the vocal cords, voiceless plosives without. Plosives are commonly voiceless, and many languages, such as Mandarin Chinese and Hawaiian, have only voiceless plosives. Others, such as most Australian languages