EDIT International Phonetic Alphabet

+ This symbol shows when a sound is spoken rhotically.
+ Example in English // water [ˈwɑːtɚ] (AE)

+ Other // This is used on the right side of a symbol to indicate an articulation involving an r-like tongue position.


Synonyms

English
+ Rhoticity Sign


+ Source //
Principles of the International Phonetic Association, London, 1949. /
Journal of the International Phonetic Association, 1989. /
Wikipedia. Die Liste der IPA-Zeichen & History of the International Phonetic Alphabet. /
Handbook of the International Phonetic Association: A Guide to the Use of the International Phonetic Alphabet. /
Pullum, Geoffrey and William A. Ladusaw. Phonetic Symbol Guide. Second edition.

 FrauFriedrich