Pre-stopped consonant

In linguistics, pre-stopping, also known as pre-occlusion or pre-plosion, is a phonological process involving the historical or allophonic insertion of a very short stop consonant before a sonorant, such as a short [d] before a nasal [n] or a lateral [l]. The resulting sounds ([ᵈn, ᵈl]) are called pre-stopped consonants, or sometimes pre-ploded or (in Celtic linguistics) pre-occluded consonants, although technically [n] may be considered an occlusive/stop without the pre-occlusion.

A pre-stopped consonant behaves phonologically as a single consonant. That is, like affricates and trilled affricates, the reasons for considering these sequences to be single consonants lies primarily in their behavior. Phonetically they are similar or equivalent to stops with a nasal or lateral release.

There are three terms for this phenomenon. The most common by far is prestopped/prestopping. In descriptions of the languages of Southeast Asia, Australia, and the Pacific, preploded/preplosion is common, though prestopped is also used. In accounts of Celtic languages, preoccluded/preocclusion is used almost exclusively. Technically, nasals are already occlusives, and are often considered stops; however, some prefer to restrict the term 'stop' for consonants in which there is complete cessation of airflow, so 'prenasalized stop' and 'prestopped nasal' are not tautologies.

In Manx, pre-occlusion occurs in stressed monosyllabic words (i.e. words one syllable long), and is also found in Cornish on certain stressed syllables. The inserted stop is homorganic with the sonorant, which means it has the same place of articulation. Long vowels are often shortened before pre-occluded sounds. In transcription, pre-occluding consonants in final position are typically written with a superscripted letter in Manx and in Cornish.

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