Is a lateral plosive a thing?

Question

Lateral (egressive) consonants are made by obstructing the path of the airstream using some part of the tongue and directing it to escape the along the sides of the mouth. This gives lateral approximants like /l/, /ʎ/, /ɫ/ etc. their distinctive sound, different than the corresponding central approximants /ɹ/~/z̞/, j etc. Of course, the same principle applies to lateral fricatives, affricates and taps, which find use in a lot of languages. However, I have never seen a mention of lateral plosives. To me, it seems that they should exist – at least in principle. In fact, I think I can make what seem to be lateral plosives and even ejectives! So, is there really some physiological reason that makes lateral plosives impossible (i.e., what I am producing are something else), or are they never mentioned because no (living, known, attested, well-documented) language uses them?

Along the same lines, I have seen some stuff on laterally released (IPA /◌ˡ/) plosives, such as the -ddle in middle [ˈmɪdˡɫ̩]. Is this what I am calling a lateral plosive?

Answer 1

This is basically a terminological problem. It is sometimes said that there are no lateral plosives, because you don't see any lateral plosive letter in the IPA row for plosives. Plosives are categorized in terms of the place where the constriction is, and "lateral" isn't considered a place, it's termed a "manner". That's not totally inappropriate, since plain stops and affricates are (reasonably) classified differently, and lateral release is very similar to fricative release in its acoustic realization. If you change from IPA terminology to the terminology of phonological theory, plain stops (plosives) and affricates (including lateral affricates) have something in common: they stop airflow through the oral cavity, and are treated as "stops". They differ in how they are released, so affricates (including lateral affricates) are stops with something else. (It is still not resolves what that something else is). There are a decent enough number of languages with lateral affricates, for example Lushootseed, Tlingit, Haida, Sotho.

In the case of "middle", however, it is better to treat the word as disyllabic, with syllabic [l̩] as the peak of the second syllable (whose onset of [d]).

Answer 2

Coincidentally, the page of Preliminaries to Linguistic Phonetics (1971) by Peter Ladefoged that I cited recently in my answer to Is there a voiced-unvoiced pair for R or L in any language? actually has something to say about this:

Table 33 includes some items labeled lateral stops. In this label it might appear that the term lateral is being used in an unusual way; but the best way of distinguishing between the sounds at the beginning of the Zulu words for pound and dress up is by calling one of them an alveolar lateral click and the other an alveolar central click. It is theoretically possible to regard these items as sequences, but of which segments I am not at all clear. Consequently in practice it seems difficult to avoid applying the terms central and lateral to clicks; and once the practice has been established of regarding certain stop consonants (the clicks) as central or lateral, it seems logical to extend this usage to ejectives (and, in other languages, to implosives and plosives). There is clearly a physiological unity to ejective laterals (such as Zulu cʎ̥’ and the more common tl̥’ which forms part of the ejective series in many Amerindian languages such as Navajo). It is very difficult to describe these gestures as sequences of two other gestures. So we may regard the central-lateral distinction as an additive component for stops, as well as for fricatives, approximants, and flaps. When used in relation to stops this opposition specifies not just the manner of the sound after the closure, but more especially the place of release of the closure. (53-54)

(bolding added)

From what this passage says, it sounds like "ˡ" would indeed signify what Ladefoged refers to as lateral plosives. Of course, different phoneticians might have different opinions. The Wikipedia page on "Navajo phonology" transcribes the lateral stop series as affricates, except for the plain unaspirated one ("tˡ tɬʰ tɬʼ").

Here is the table mentioned:

Table 33 Contrasts involving laterals in Zulu (suggested by L.W. Lanham). All these items are imperative forms of verbs, all with a sequence of low tone followed by high tone.

                                               Voiced        Voiceless 
Alveolar lateral approximant                   londa
                                               preserve
Alveolar lateral fricative                     ɮuɮa          ɬoɬa
                                               roam loose    prod
Alveolarlateral velaric stop (click)           g͡ʖoba         ʖoʖa
                                               pound         narrate
Palatal lateral glottalic stop (ejective)      cʎ’ecʎ’a
                                               tattoo
Postalveolar central velaric stop (click)      g͡ʗoka         ʗaʗa
                                               dress up      explain

(54)

(rotated 90 degrees to fit better)