Liquid

From KneeQuickie

Liquids are a class of consonants consisting of all approximants that are not semivowels; this therefore includes lateral approximants and rhotics.

The presence of liquids is common in languages, but it is rare for a language to contain more than a few.

Liquids, like all sonorants, are usually voiced, and indeed, the IPA only has separate symbols for voiced liquids.

(See the article approximant for a chart of IPA and X-Sampa symbols for liquids.)