O, Octonion, Fraktur, Unicode subscripts and superscripts, Enclosed Alphanumeric Supplement, Ordinal indicator, Enclosed Alphanumerics, Ö, Õ, Ó, Ɵ, Ǫ, Open-mid back rounded vowel, Mid back rounded vowel, Oʻ, Ø, Ò, Ơ, Ꝍ, Inverted breve, Mid front rounded vowel, Open O, O', O͘, Breve, ⱺ, Macron (diacritic), Vietnamese alphabet, Ǫ́, Circumflex, Ogonek, Dot (diacritic), R-colored vowel, Finno-Ugric transcription, Bilabial click, Nasal vowel, Double grave accent, Hook above, Diethyl ether, Double acute accent, Scribal abbreviation

International Phonetic Alphabet, Ring (diacritic), Shift Out and Shift In characters, Cedilla, Mid central vowel, Livonian language, Nasal bilabial click, Caron, Small caps, O,O′-Diacetyldopamine, P&O, O,O′-Dipivaloyldopamine, O visa, O (disambiguation), O-methylated flavonoid, O Antiphons, O A e o Z, O-GlcNAc, Douglas O-38, O-Acetylbufotenine, O class, O line, O-Pivalylbufotenine, O series, Pui O, O lucenti, o sereni occhi, Big O, Big O notation, O Come, O Come, Emmanuel, O. Henry Award, Tai O, Ping-O-Tronic, O (Cyrillic), Haplogroup O-M119, O Tannenbaum, O-ring, Ó Paí, Ó, O Tempo e o Vento, Isoflavone-7-O-beta-glucoside 6"-O-malonyltransferase, O-type star, P&O Cruises, O-linked glycosylation, O-demethylpuromycin O-methyltransferase, O le Ao o le Malo, Flavonol-3-O-beta-glucoside O-malonyltransferase, P&O Princess Cruises, Kamen Rider Den-O + Shin-O, Ó Rothláin, Pig-hoo-o-o-o-ey, O-Acetylserine

O, Octonion, Fraktur, Unicode subscripts and superscripts, Enclosed Alphanumeric Supplement, Ordinal indicator, Enclosed Alphanumerics, Ö, Õ, Ó, Ɵ, Ǫ, Open-mid back rounded vowel, Mid back rounded vowel, Oʻ, Ø, Ò, Ơ, Ꝍ, Inverted breve, Mid front rounded vowel, Open O, O', O͘, Breve, ⱺ, Macron (diacritic), Vietnamese alphabet, Ǫ́, Circumflex, Ogonek, Dot (diacritic), R-colored vowel, Finno-Ugric transcription, Bilabial click, Nasal vowel, Double grave accent, Hook above, Diethyl ether, Double acute accent, Scribal abbreviation, International Phonetic Alphabet, Ring (diacritic), Shift Out and Shift In characters, Cedilla, Mid central vowel, Livonian language, Nasal bilabial click, Caron, Small caps, O,O′-Diacetyldopamine, P&O, O,O′-Dipivaloyldopamine, O visa, O (disambiguation), O-methylated flavonoid, O Antiphons, O A e o Z, O-GlcNAc, Douglas O-38, O-Acetylbufotenine, O class, O line, O-Pivalylbufotenine, O series, Pui O, O lucenti, o sereni occhi, Big O, Big O notation, O Come, O Come, Emmanuel, O. Henry Award, Tai O, Ping-O-Tronic, O (Cyrillic), Haplogroup O-M119, O Tannenbaum, O-ring, Ó Paí, Ó, O Tempo e o Vento, Isoflavone-7-O-beta-glucoside 6"-O-malonyltransferase, O-type star, P&O Cruises, O-linked glycosylation, O-demethylpuromycin O-methyltransferase, O le Ao o le Malo, Flavonol-3-O-beta-glucoside O-malonyltransferase, P&O Princess Cruises, Kamen Rider Den-O + Shin-O, Ó Rothláin, Pig-hoo-o-o-o-ey, O-Acetylserine, Daddy-O, O-Bi, O-Ba: The End of Civilization, Ó Lochlainn, Google I/O, Cyanidin 3-O-rutinoside 5-O-glucosyltransferase, Asynchronous I/O, Protein O-GlcNAcase, Ó Sé, Vitexin 2"-O-rhamnoside 7-O-methyltransferase, Lycoming O-235, O-type main-sequence star, Cyanidin-3-O-glucoside 2-O-glucuronosyltransferase, Delphinidin 3',5'-O-glucosyltransferase, Tam o' Shanter, Anthocyanin 3-O-glucoside 6''-O-hydroxycinnamoyltransferase, Anti-streptolysin O, O (German magazine), Memory-mapped I/O and port-mapped I/O, O scale, Haplogroup O-M175, HNLMS O 20, Yeshe-Ö, Cyrillic O variants, Jack-o'-lantern, W/o, P&O Ferries, O... Saya, USS O-12, The Big O, Shibuya O-East, Double-O, Subdwarf O star, Séamus Ó Fearghail, O tempora, o mores!, Continental O-200, Handley Page Type O, Yam O, Te Pīhopatanga o Te Upoko o Te Ika, Te o Tsunagō/Ai o Utaō, Domnall Ó Cuindlis, Bit-O-Honey, THC-O-acetate, O Silêncio Q Precede O Esporro, Lycoming O-290, USS O-7, 'O pere e 'o musso, I/O scheduling, Heme O, Te Pīhopatanga o Te Manawa o Te Wheke, O‑Level, Anthocyanin 5-O-glucoside 6'''-O-malonyltransferase, Douglas O-2, Beta-glucogallin O-galloyltransferase, Jell-O Gallery, O-Zone, Punk-O-Rama, O, The Oprah Magazine, Páidí Ó Sé, Ádhamh Ó Cianáin, Man o' war