Rhotic consonant

In phonetics, rhotic consonants, or "R-like" sounds, are liquid consonants that are traditionally represented orthographically by symbols derived from the Greek letter rho, including ⟨R⟩, ⟨r⟩ in the Latin script and ⟨Р⟩, ⟨p⟩ in the Cyrillic script. They are transcribed in the International Phonetic Alphabet by upper- or lower-case variants of Roman ⟨R⟩, ⟨r⟩:r, ɾ, ɹ, ɻ, ʀ, ʁ, ɽ, and ɺ.

This class of sounds is difficult to characterise phonetically; from a phonetic standpoint, there is no single articulatory correlate common to rhotic consonants. Rhotics have instead been found to carry out similar phonological functions or to have certain similar phonological features across different languages. Although some have been found to share certain acoustic peculiarities, such as a lowered third formant, further study has revealed that this does not hold true across different languages. For example, the acoustic quality of lowered third formants pertains almost exclusively to American varieties of English. Being "R-like" is an elusive and ambiguous concept phonetically and the same sounds that function as rhotics in some systems may pattern with fricatives, semivowels or even stops in others—for example, "tt" in American English "better" is often pronounced as an alveolar tap, a rhotic consonant in many other languages.

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