This article is about the sound in spoken language. For the letter, see glottal stop (letter).

IPA – number	113
IPA – text	ʔ
IPA – image
Entity	ʔ
X-SAMPA	?
Kirshenbaum	?
Sound sample (help·info)

The glottal stop, or more fully, the voiceless glottal plosive, is a type of consonantal sound which is used in many spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ʔ. The glottal stop is the sound made when the vocal cords (vocal folds) are (1) drawn together by muscular action to interrupt the flow of air being expelled from the lungs and then (2) released as pressure builds up below them; for example, the break separating the syllables of the interjection uh-oh. Strictly, the perception that it is a consonantal sound is produced by the release; the closure phase is necessarily silent because during it there is no airflow and the vocal cords are immobilized. It is called the glottal stop because the technical term for the gap between the vocal cords, which is closed up in the production of this sound, is the glottis. The term "glottal stop" is one of rather few technical terms of linguistics which have become well known outside the specialism.

Phonology and symbolization of the glottal stop in selected languages

While this segment is not a phoneme in English, it is present phonetically in nearly all dialects of English as an allophone of /t/. Most British English speakers will use it for the first "t" in fortnight, where a consonant follows immediately; speakers of Cockney and many other dialects will also use it for the "t" between vowels in city. It is variably present at word boundaries where a vowel follows at the beginning of the next word, as with the final "t" of "sort" in sort of.

Another common usage of the glottal stop as an allophone to 't' more commonly found in North America is in the environment in which the 't' is immediately followed by a non-syllabic 'n' sound, as in mutant or important.

In many languages which do not allow a sequence of spoken vowel sounds, such as Persian, the glottal stop may be used to break up such a sequence. There are intricate interactions between falling tone and the glottal stop in the histories of such languages as Danish (cf. stød), Chinese and Thai.

In the traditional Romanization of many languages, such as Arabic, the glottal stop is transcribed with an apostrophe, <’>, and this is the source of the IPA letter <ʔ>. In many Polynesian languages which use the Latin alphabet, however, the glottal stop is written with a reversed apostrophe, <‘> (called ‘okina in Hawaiian), which, confusingly, is also used to transcribe the Arabic ayin and is the source of the IPA character for the voiced pharyngeal fricative <ʕ>. In Malay, it is represented by the letter <k>, and in Võro and Maltese by <q>. Representing the glottal stop is one of the functions of the Hebrew letter aleph.

In the graphic representation of most Philippine languages, the glottal stop has no consistent symbolization. In most cases, however, a word that begins with a vowel-letter (e.g. Tagalog aso 'dog') is always pronounced with an unrepresented glottal stop before that vowel (as also in Modern German and Hausa). Some orthographies employ a hyphen, instead of the reverse apostrophe, if the glottal stop occurs in the middle of the word (e.g. Tagalog pag-ibig 'love'). When it occurs in the end of a Tagalog word, the last vowel is written with a circumflex accent (if the accent is on the last syllable) or a grave accent (if the accent occurs at the penultimate syllable).

Phonetic and phonological features

Features of the glottal stop:

• Its airstream mechanism is pulmonic egressive, which means it is articulated by pushing air out of the lungs and through the vocal tract, rather than being initiated from the glottis or from a velic closure.
• Its place of articulation is glottal which means it is articulated at and by the vocal cords (vocal folds).
• Its manner of articulation is plosive or stop, which means it is produced by completely obstructing the airflow in the vocal tract.
• Its phonation type is voiceless, which means it is produced without vibration of the vocal cords; necessarily so, because the vocal cords are held tightly together, preventing vibration.
• It is an oral consonant, which means the air released when the closure is relaxed is allowed to escape through the mouth rather than the nasal cavity.
• Because it is pronounced in the larynx, situated in the windpipe; i.e. it has no component involved in the description of movements of the organs of the mouth, for example the tongue, so the central/lateral dichotomy does not apply, and nor do the tongue-front features such as coronal and distributed.

Occurrence

See also

• List of phonetics topics
• Stød in Danish
• Saltillo (linguistics)

References

Bibliography

• Blevins, Juliette (1994), "The Bimoraic Foot in Rotuman Phonology and Morphology", Oceanic Linguistics 33(2): 491-516 
• Gussenhoven, Carlos (1992), "Dutch", Journal of the International Phonetic Association 22 (2): 45-47 
• Roach, Peter (2004), "British English: Received Pronunciation", Journal of the International Phonetic Association 34 (2): 239-245 
• Schane, Sanford A (1968), French Phonology and Morphology, Boston, Mass.: M.I.T. Press 
• Sivertsen, Eva (1960), Cockney Phonology, Oslo: University of Oslo 
• Thelwall, Robin (1990), "Illustrations of the IPA: Arabic", Journal of the International Phonetic Association 20 (2): 37-41 
• Watson, Janet (2002), The Phonology and Morphology of Arabic, New York: Oxford University Press