Word Study
Rhotacism
CIDE DICTIONARY
Rhotacism, n. [Gr. "rwtaki`zein to use the letter r (rhotacisme.].
An oversounding, or a misuse, of the letter r; specifically (Phylol.) , the tendency, exhibited in the Indo-European languages, to change s to r, as wese to were. [1913 Webster]
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