Friday, 13 April 2012

implosives and ejectives

In modern phonetic terminology, an ‘implosive’ is a sound made with a glottalic ingressive airstream mechanism. That is, the airstream is initiated by sharply lowering the glottis, thereby creating negative pressure in the supraglottal cavity. However implosives are typically voiced, with simultaneous vibration of the vocal cords through pressure from the pulmonic cavities. So you could say that they have a mixed glottalic ingressive and pulmonic egressive airstream mechanism. The IPA chart lists five symbols for implosives, all voiced: ɓ ɗ ʄ ɠ ʛ. There are also voiceless implosives, produced purely with the ingressive glottalic airstream mechanism.

Examples from relatively familiar languages are the ɓ ɠ of Zulu and the ɓ ᶑ ʄ ɠ of Sindhi (the second of these is retroflex). According to Ladefoged and Maddieson (The Sounds of the World’s Languages, Blackwell 1996), the Igbo labialvelar spelt gb, often considered a voiced pulmonic plosive with double articulation, i.e. simultaneous b and g, is more accurately described as a voiceless bilabial implosive, ɓ̥.

In the WALS data, implosives are found in 75 of the 567 languages studied (= 13%), most of them in Africa or southeast Asia. (Ladefoged and Maddieson, however, say that implosives are found in “about 10% of the world’s languages”.) By far the commonest implosive is the voiced bilabial ɓ.

The OED reveals that as a phonetic term ‘implosive’ goes back at least as far as Sweet, who wrote in 1890 that
Some sounds are produced without either out- or in-breathing, but solely with the air in the throat or mouth. The ‘implosives’ are formed in the former, the suction-stops or ‘clicks’ in the latter way.

There is one other usage you may occasionally come across in older works, in which an ‘implosive’ stop is an ordinary pulmonic stop with no audible release stage, or in which the release is not taken into account, as against an ‘explosive’ one which has no audible approach stage, or in which the approach stage is not taken into account. The OED has a quotation from Bazell in 1953:
If all initial occlusives are explosive and all final occlusives are implosive, it is obvious that two distinct conventions (explosiveness of initials and implosiveness of finals) need not be postulated.
We can regard this meaning as obsolete.

We pair implosives with ‘ejectives’, sounds made with a glottalic egressive airstream mechanism. They have an airstream initiated by the raising of the closed glottis, which compresses the air in the supraglottal cavity. The OED’s first citation for this term is Daniel Jones in 1932.

In IPA ejectives are written with an apostrophe diacritic, thus pʼ tʼ kʼ etc. They are “not at all unusual sounds, occurring in about 18 percent of the languages of the world” (L & M). Although they are not contrastive in English or any other European language, many speakers in Britain use ejectives as optional phrase-final variants of p t k.

I made a Google ngram for these two terms. Rather mysteriously, it shows implosive ejective peaking in 1900, while ejective implosive does not come onto the scene until 1920, peaking in 1970. I wonder what the explanation for this is.


  1. For 'ejective' around 1970, maybe the glottalic theory of Proto-Indo-European stops?

    1. Actually, looking at the n-gram again, isn't it 'ejective' which peaks around 1900, 'implosive' around 1970?

    2. I've just noticed the same thing, and amended the text accordingly. Very curious.

  2. Mightn't "implosive" be a physical term, too?

    1. Well yes, obviously. These stats can hardly reflect the phonetic use of the two words, so they must be other uses.

  3. If you follow your link to the "ngram", below the graph are some date ranges you can click on. Clicking on 1901-1904 for "ejective" (around the peak), it seems that not one of the usage examples that it finds relate to phonetics; many relate to philosophy or psychology. I didn't investigate these in detail, but I do see that the OED gives other meanings of "ejective" with earlier citations. Rerunning the search to include the word "consonant" (results) gives both peaking in the later period, though obviously the number of hits is then that much smaller.

  4. I am studying for an oral phonetic exam in York, and my favorite sounds to practice are the ejectives and implosives. I even made a youtube video to show my mom what all my university time and money go towards, and now its the 7th google result for 'ejectives and implosives.' This post is now the 2nd. :)

  5. The OED gives only two senses of implosive: the phonetic, and the one which probably accounts for the peak in the 1970's.

    The latter is first recorded in 1964 in the writing of Marshal McLuhan — who may well have invented it. McLuhan liked to make a contact between explosive and implosive processes, which might be movements from and to a centre, or might be sudden great increases or decreases.

    The OED labels this use as fig(urative) and refers to a figurative use of the noun implosion. This, too, was used by McLuhan in 1964 and contrasted with an equally figurative explosion. In the case of the noun, he wasn't the first. In 1960 JG Ballard wrote comparing an expected Mathusian population explosion with an actual population implosion in Sumatra.

    The non-figurative sense of implosion — what light bulbs do when you smash them — seems to have been invented around 1880. I take it that it described what happened to laboratory apparatus that had not previously been widely available for use and observation.

    No record of the adjective as applicable to what happens to light bulbs. And no other use of either noun or adjective in any other sense from the 1920's. Presumably, there was a technical use (or several uses) in a register that the OED does not attempt to cover.

    The entry for ejective is a surprise. It was for a long time a medical or semi-medical term now replaced entirely by emetic. There is, of course, the phonetic sense. And then there's the philosophical sense. To understand this, I think the best starting point is the first quote (WK Clifford 1878) in the entry for the noun eject:

    I propose‥to call these inferred existences ejects, things thrown out of my consciousness, to distinguish them from objects, things presented in my consciousness, phenomena.

    This reads like a personal invention made by somebody who knew his Latin.