Obstruent

In phonetics, an obstruent (/ˈɒb.stru.ənt/, OB-stroo-ənt) is a speech sound that is formed by obstructing airflow, such as [d] (plosives/oral stops), [ʒ] (fricatives), or [d͡ʒ] (affricates). Obstruents contrast with sonorants, which have no such obstruction and therefore "resonate". All obstruents are consonants, but sonorants include vowels as well as consonants. As a distinctive feature, obstruents are denoted as [−son].

Compare occlusives, a class of speech sounds which includes both oral and nasal stops as well as affricates, but excludes fricatives, and contrasts with continuants.