Retroflex sounds are produced by the curling the tip of the tongue backwards just behind the alveolar ridge. Many speakers of English produce the r sound [ɹ] as a retroflex consonant: [ɻ]. In this case, it is an example of free variation and does not alter the meaning of the word in which it appears. Like English, retroflexivity is not phonemic and Gaelic, however <rr> is often produced as retroflex.
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- Crystal, David. (1997) A Dictionary of Linguistics and Phonetics. Oxford, UK: Blackwell.
- Ladefoged, D. (2010) A Course in Phonetics. 6th Edition. Wadsworth Publishing.