Glottal stop

The glottal stop, or more fully, the voiceless glottal plosive, is a type of consonantal sound used in many spoken languages produced by obstructing airflow in the vocal tract. In English, the feature is represented, for example, by the hyphen in uh-oh! and by the apostrophe or ʻokina in Hawaii among those using a preservative pronunciation of that name.

The symbol in the International Phonetic Alphabet that represents this sound is ⟨⟩. It is called the glottal stop because the technical term for the gap between the vocal folds, which is closed up in the production of this sound, is the glottis.

Phonetic and phonological features
Features of the glottal stop:


 * Its phonation 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.

Phonology and symbolization of the glottal stop in selected languages
While this segment is not a written phoneme in English, it is present phonetically in nearly all dialects of English as an allophone of  in the syllable coda. Speakers of Cockney, Scottish English and several other British dialects also pronounce an intervocalic between vowels as in city. Standard English inserts a glottal stop before a tautosyllabic voiceless plosive, e.g. sto’p, tha’t, kno’ck, wa’tch, also lea’p, soa’k, hel’p, pin’ch.

In many languages that don't allow a sequence of vowels, such as Persian, the glottal stop may be used to break up such a hiatus. 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 character ⟨⟩. In many Polynesian languages that 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 ⟨⟩. In Malay the glottal stop is represented by the letter ⟨k⟩, in Võro and Maltese by ⟨q⟩.

Other scripts also have letters used for representing the glottal stop, such as the Hebrew letter aleph ⟨א⟩, and the Cyrillic letter palochka ⟨Ӏ⟩ used in several Caucasian languages. In Tundra Nenets it is represented by the letters apostrophe ⟨⟩ and double apostrophe ⟨⟩. In Japanese, glottal stops occur at the end of interjections of surprise or anger, and are represented by the character っ.

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).

Some Canadian indigenous languages have adopted the phonetic symbol "ʔ" itself as part of their orthographies. In some of them, it occurs as a pair of uppercase and lowercase characters, Glottal stop (letter).