Rhotacism (sound change)

Rhotacism (/ˈroʊtəˌsɪzəm/) or rhotacization is a sound change that converts one consonant (usually a voiced alveolar consonant: /z/, /d/, /l/, or /n/) to a rhotic consonant in a certain environment. The most common may be of /z/ to /r/.

The term comes from the Greek letter rho, denoting "r".

The southern Tosk dialects, on which modern standard Albanian is based, changed /n/ to /r/ while the northern Gheg dialects did not:

In Aramaic, Proto-Semitic n changed to r in a few words:

Ancient Basque *l changed into a tapped R between vowels in Basque. It can be observed in words borrowed from Latin; for example, Latin caelum (meaning "sky, heaven") became zeru in Basque (caelum > celu > zeru; cf. cielo in Spanish). The original l is preserved in the Souletin dialect: caelum > celu > zelü.

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