Sonorant

In phonetics and phonology, a sonorant is a speech sound that is produced without turbulent airflow in the vocal tract. Vowels are sonorants, and so are approximants, nasal consonants, taps, and trills. That is, all sounds higher on the sonority hierarchy than fricatives are sonorants.

The word resonant is sometimes used for these non-turbulent sounds. In this case, the word sonorant may be restricted to non-vocoid resonants; that is, all of the above except vowels and semivowels. However, this usage is becoming dated.

Sonorants contrast with obstruents, which do cause turbulence in the vocal tract.