O (disambiguation) Ö Ơ Õ Ø O,O′-Diacetyldopamine Ó P&O O O,O′-Dipivaloyldopamine O' O-methylated flavonoid O visa Ò O Antiphons O-GlcNAc O A e o Z Douglas O-38 Open O O class Pui O O line O series O lucenti, o sereni occhi Oʻ Big O O. Henry Award Ping-O-Tronic Tai O Big O notation O Come, O Come, Emmanuel Haplogroup O-M119 O Tannenbaum Yeshe-Ö Ó Paí, Ó Ɵ O-ring O Tempo e o Vento Ó Rothláin O (Cyrillic) P&O Cruises O-type star P&O Princess Cruises O le Ao o le Malo