The double grave accent (◌̏) is a diacritic used in scholarly discussions of the Serbo-Croatian and sometimes Slovene languages.
The double grave accent is found in both Latin and Cyrillic; however, it is not used in the everyday orthography of any language, only in discussions of phonology.
In the International Phonetic Alphabet, the double grave accent is used to indicate extra-low tone.
The letters a, e, i, o, r, u, and their Cyrillic equivalents а, е, и, о, р, and у can all be found with the double grave accent.
The Cyrillic letters can be formed using the combining character for the double grave, which is located at U+030F.