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Noun: o
  1. The 15th letter of the Roman alphabet
    - O
Noun: O  ow
  1. A nonmetallic bivalent element that is normally a colourless, odourless, tasteless, nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
    - oxygen, atomic number 8
     
  2. The blood group whose red cells carry neither the A nor B antigens
    "people with type O blood are universal donors";
    - type O, group O
Interjection: O  ow
  1. Used to express surprise
    "O, it was only a dollar last time I was here!";
    - Christ [informal], Christmas [informal], crikey [Brit, informal], cripes [informal], cor [Brit, informal], crumbs [Brit, informal], gosh [informal], golly [informal], by George [informal], by Jove [informal], blimey [Brit, informal], gorblimey [Brit, informal], cor blimey [Brit, informal], my [informal], holy cow [informal], holy mackerel [informal], holy smoke [informal], holy moley [informal], holy moly [informal], fancy [Brit, informal], good grief [informal], goodness [informal], goodness me [informal], Gordon Bennett [informal], gracious [informal], gracious me [informal], fancy that [informal], gawd [informal], god, my word, oh, ah, oh boy [informal], jeez [informal], geez [informal], strewth [Brit, informal], struth [Brit, informal], yikes [informal], I'll be blowed [Brit, informal], blow me [Brit, informal], Holy-dooly [Austral, informal], heck [informal], blooming heck [Brit, informal], jeepers [informal], jeepers creepers [informal], Lord [informal], Lordy [informal], marry [archaic], well I never [informal], heavens [informal], good heavens [informal], my goodness [informal], Jesus [informal], bejesus [N. Amer, informal], od [archaic]

Derived forms: os, Os

Type of: alphabetic character, blood group, blood type, chemical element, element, gas, letter, letter of the alphabet

Part of: air, H2O, Latin alphabet, ozone, Roman alphabet, water

Encyclopedia: O, Yeah! The Ultimate Aerosmith Hits