Its phonation is voiced, which means the vocal cords vibrate during the articulation. However, in some languages (like Swiss German) it can just mean that this consonant is pronounced shorter and weaker than its voiceless counterpart, while its voicedness or lack thereof is not relevant. In such cases it's more accurate to call such sounds lenis or lax.
It is an oral consonant, which means air is allowed to escape through the mouth only.
It is a central consonant, which means it is produced by directing the airstream along the center of the tongue, rather than to the sides.
Allophone of [ɾ ~ ʁ] in recent loanwords, used even by many speakers who do not use coda alveolar, post-alveolar or retroflex approximants in native words. Varies individually. Generally not as onset or final e.g. trailer[ˈtɾejle̞ʁ].
Some or all coda /ɾ/ may instead be a guttural or an approximant, varying by speaker, albeit more likely to be aspirated or deleted altogether than to be an approximant among native speakers when as final. See Portuguese phonology.
Allophone of [ɾ ~ ʁ] in the syllable coda. May also be retroflex, post-alveolar and/or rhotic vowel. As most rhotic coda in colloquial Brazilian Portuguese, likely to get deleted as final or at the end of sentences
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