Preaspiration

In phonetics, preaspiration (sometimes spelled pre-aspiration) is a period of voicelessness or aspiration preceding the closure of a voiceless obstruent, basically equivalent to an [h]-like sound preceding the obstruent. In other words, when an obstruent is preaspirated, the glottis is opened for some time before the obstruent closure. To mark preaspiration using the International Phonetic Alphabet, the diacritic for regular aspiration, ⟨ʰ⟩, can be placed before the preaspirated consonant. However, Ladefoged & Maddieson (1996) prefer to use a simple cluster notation, e.g. ⟨hk⟩ instead of ⟨ʰk⟩.

Preaspiration is comparatively uncommon across languages of the world, and is claimed by some to not be phonemically contrastive in any language.Ladefoged & Maddieson (1996) note that, at least in the case of Icelandic, preaspirated stops have a longer duration of aspiration than normally aspirated (post-aspirated) stops, comparable to clusters of [h]+consonant in languages with such clusters. As a result, they view preaspiration as purely a distributional feature, indistinguishable phonetically and phonologically from clusters with /h/, and prefer to notate preaspirated stops as clusters, e.g. Icelandic kappi /ˈkʰahpi/ "hero" rather than /ˈkʰaʰpi/.

A distinction is often made between so-called normative and non-normative preaspiration: in a language with normative preaspiration of certain voiceless obstruents, the preaspiration is obligatory even though it is not a distinctive feature; in a language with non-normative preaspiration, the preaspiration can be phonetically structured for those who use it, but it is non-obligatory, and may not appear with all speakers. Preaspirated consonants are typically in free variation with spirant-stop clusters, though they may also have a relationship (synchronically and diachronically) with long vowels or [s]-stop clusters.

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