Liquid consonant

In phonetics, liquids or liquid consonants are a class of consonants consisting of lateral consonants like 'l' together with rhotics like 'r'.

Liquids as a class often behave in a similar way in the phonotactics of a language: for example, they often have the greatest freedom in occurring in consonant clusters. In many languages, such as Japanese and Korean, there is a single liquid phoneme that has both lateral and rhotic allophones.

English has two liquid phonemes, one lateral, /l/ and one rhotic, /ɹ/, exemplified in the words led and red.

Many other European languages have one lateral and one rhotic phoneme. Some, such as Greek, Italian and Serbo-Croatian, have more than two liquid phonemes. All three languages have the set /l/ /ʎ/ /r/, with two laterals and one rhotic. Similarly, the Iberian languages contrast four liquid phonemes. /l/, /ʎ/, /ɾ/, and a fourth phoneme that is an alveolar trill in all but some varieties of Portuguese, where it is a uvular trill or fricative. Some European languages, like Russian and Irish, contrast a palatalized lateral–rhotic pair with an unpalatalized (or velarized) set (e.g. /lʲ/ /rʲ/ /l/ /r/ in Russian).

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