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

l Phonetic Alphabet Nasal bilabial click Caron P&O O-methylated flavonoid O visa O (disambiguation) O Antiphons O A e o Z O-GlcNAc Douglas O-38 O class Pui O O series O line Big O O lucenti, o sereni occhi O Tempo e o Vento O. Henry Award Tai O Ping-O-Tronic Big O notation O Come, O Come, Emmanuel Haplogroup O-M119 O-ring O Tannenbaum Yeshe-Ö Ó Paí, Ó O le Ao o le Malo P&O Princess Cruises O (Cyrillic) Ó Rothláin O-type star