- rhotacism (n.)
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- 1830, from Modern Latin rhotacismus, from Greek rhotakizein, from rho "the letter -r-," from Hebrew or Phoenician roth. Excessive or peculiar use of the -r- sound (the "burr"), especially the conversion of another sound (usually -s-) to -r-; as in Aeolian Greek, which at the end of words changed -s- into -r- (hippor for hippos, etc.). Related: Rhotacize.