[1] However, they occur in two of the most widely spoken languages: North American English and Mandarin Chinese.

In North American English, they are found in words such as dollar, butter, third, color, and nurse.

They also occur in Canadian French, some varieties of Portuguese,[2][3][4] some Jutlandic dialects of Danish, and in a few indigenous languages of the Americas and of Asia, including Serrano and Yurok in the United States, Luobohe Miao in China, Katë in Afghanistan, and Badaga in India.

[5] Both ⟨ɚ⟩ and ⟨ɝ⟩ were proposed as IPA symbols by the editors of American Speech in 1939 to distinguish it from [əɹ].

[10] Following the convention of alternating ⟨ɜ⟩ and ⟨ə⟩ for non-rhotic accents, ⟨ɝ⟩ and ⟨ɚ⟩ signify stressed and unstressed, respectively, rather than a difference in phonetic quality.

[citation needed] Certain post-grunge singers made heavy use of this technique to such an extent that many people derisively exaggerated this tendency when referencing their music.

[13] Major cities that have this form of rhotacized ending include Beijing, Tianjin, Tangshan, Shenyang, Changchun, Jilin, Harbin, and Qiqihar.

This erhua has since spread to other provincial capitals not home to Standard Mandarin, such as Shijiazhuang, Jinan, Xi'an, Chongqing, and Chengdu.

In rhotic accents of Standard Mandarin, such as those from Beijing, Tianjin, most of the Hebei province (e.g. Tangshan, Baoding, Chengde), eastern Inner Mongolia (e.g. Chifeng, Hailar), and in the Northeast, vocalic r occurs as a diminutive marker of nouns (pinyin: ér) and the perfective aspect particle (了; le).