Open-mid back rounded vowel Ö Ɵ Ò O Ó Ǫ Breve Oʻ Mid back rounded vowel Inverted breve Õ Ơ ⱺ Mid front rounded vowel O͘ Ǫ́ Open O Ø O' Circumflex Unicode subscripts and superscripts Vietnamese alphabet Ꝍ Bilabial click Macron (diacritic) Diethyl ether Double grave accent Livonian language Dot (diacritic) Ordinal indicator Ogonek Mid central vowel Scribal abbreviation International Phonetic Alphabet Double acute accent Hook above Nasal vowel Cedilla Uralic Phonetic Alphabet R-colored vowel Shift Out and Shift In characters Octonion Fraktur Ring (diacritic) Enclosed Alphanumerics Enclosed Alphanumeric Supplement Nasal bilabial click Small caps Caron P&O O visa O-methylated flavonoid O (disambiguation) O A e o Z …

O Antiphons Douglas O-38 Oly O-GlcNAc O class O line O lucenti, o sereni occhi O series Pui O Big O O. Henry Award O Tempo e o Vento Tai O O Come, O Come, Emmanuel Big O notation Ping-O-Tronic Yeshe-Ö O Tannenbaum Haplogroup O-M119 Ó Paí, Ó O-ring O le Ao o le Malo Ó Rothláin O (Cyrillic)