Glottalization is the complete or partial closure of the
glottis during the articulation of another sound. Glottalization of
vowels and
voiced consonants is most often realized as
creaky voice (partial closure). Glottalization of voiceless consonants usually involves complete closure of the
glottis; another way to describe this phenomenon is to say that a
glottal stop is made simultaneously with another
consonant. In certain cases, the glottal stop can even wholly replace the voiceless consonant.
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