| Voiceless alveolar trill | |||
|---|---|---|---|
| r̥ | |||
| IPA Number | 122 402A | ||
| Audio sample | |||
| Encoding | |||
| X-SAMPA | r_0 | ||
| |||
The voiceless alveolar trill differs from the voiced alveolar trill /r/ only by the vibrations of the vocal cord. It occurs in a few languages, usually alongside the voiced version, as a similar phoneme or an allophone.
Proto-Indo-European *sr developed into a sound spelled ⟨ῥ⟩, with the letter for /r/ and the diacritic for /h/, in Ancient Greek. It was probably a voiceless alveolar trill and became the regular word-initial allophone of /r/ in standard Attic Greek that has disappeared in Modern Greek.
- PIE *srew- > Ancient Greek ῥέω "flow", possibly [r̥é.ɔː]