Cross-linguistically, rhotics exhibits a wide range of pronunciation variation, especially word-finally. The languages compared in this study include Turkish, Uzbek, Kazakh, Farsi, Russian, Romanian, Macedonian, Czech, Irish, and Mexican Spanish, which all have been described as having a fricative-like variant of their rhotic(s). Previous research has reported a word-final devoiced and fricated alveolar tap for Turkish and Uzbek; dentalized alveolar trill and voiced uvular fricative for Kazakh; alveolar trill, approximant, and tap which may be fricated word-finally for Farsi; alveolar and palatalized trill for Russian and Romanian; alveolar trill for Macedonian; alveolar trill with a fricated variant for Czech; palatalized tap which may be fricated for Irish; and alveolar tap with a fricated variant for Mexican Spanish. The data used for this cross-linguistic corpus study is from the Mozilla Common Voice corpus. This exploratory analysis will examine spectral differences within and across languages for each rhotic. The results of this study aim to assess the range of descriptions used for rhotics and their variants.
Miklas et al. (2025) studied this question.