In phonetics, a continuant is a speech sound produced without a complete closure in the oral cavity. By one definition, continuant is a distinctive feature that refers to any sound produced with an incomplete closure of the vocal tract, thus encompassing all sounds (including vowels) except nasals, plosives and affricates.[1][2][3][4][5] By another definition, it refers exclusively to consonantal sounds produced with an incomplete closure of the oral cavity, prototypically approximants and fricatives,[6][7] but sometimes also trills.[8]
Compare sonorants (resonants), a class of speech sounds which includes vowels, approximants and nasals (but not fricatives), and contrasts with obstruents.