What does O mean?

Definitions for O

Here are all the possible meanings and translations of the word O.

Princeton's WordNet

  1. oxygen, O, atomic number 8(noun)

    a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust

  2. O, o(noun)

    the 15th letter of the Roman alphabet

  3. O, type O, group O(noun)

    the blood group whose red cells carry neither the A nor B antigens

    "people with type O blood are universal donors"


  1. o(Noun)

    A zero .

  2. o(Interjection)

    The English vocative particle, used before a pronoun or the name of a person or persons to mark direct address.

  3. o(Interjection)


  4. o(Interjection)

    Object, see SVO

  5. o


  6. O(Noun)

    A blood type that lacks A or B antigens and may only receive transfusions of similar type O blood, but may donate to all (neglecting Rh factor). Synonym: universal donor.

  7. O(Noun)

    American Library Association

  8. O

    Someone associated with Leyton Orient Football Club, as a player, coach, supporter etc.

  9. O(Prefix)

    descendant of; used to form Irish patronymic surnames.


  1. O

    O (named o, plural oes) is the 15th letter and the fourth vowel in the modern English alphabet and the ISO basic Latin alphabet.

Webster Dictionary

  1. O

    o, the fifteenth letter of the English alphabet, derives its form, value, and name from the Greek O, through the Latin. The letter came into the Greek from the Ph/nician, which possibly derived it ultimately from the Egyptian. Etymologically, the letter o is most closely related to a, e, and u; as in E. bone, AS. ban; E. stone, AS. stan; E. broke, AS. brecan to break; E. bore, AS. beran to bear; E. dove, AS. d/fe; E. toft, tuft; tone, tune; number, F. nombre

    Etymology: [See One.]

  2. O

    among the ancients, O was a mark of triple time, from the notion that the ternary, or number 3, is the most perfect of numbers, and properly expressed by a circle, the most perfect figure

    Etymology: [See One.]

  3. O(noun)

    the letter O, or its sound

    Etymology: [See One.]

  4. O(noun)

    something shaped like the letter O; a circle or oval

    Etymology: [See One.]

  5. O(noun)

    a cipher; zero

    Etymology: [See One.]

  6. O(adj)


    Etymology: [See One.]

  7. O

    an exclamation used in calling or directly addressing a person or personified object; also, as an emotional or impassioned exclamation expressing pain, grief, surprise, desire, fear, etc

    Etymology: [See One.]


  1. O

    O is the fifteenth letter and a vowel in the ISO basic Latin alphabet.

Chambers 20th Century Dictionary

  1. O

    oh, ō, interj. an exclamation of wonder, pain, desire, fear, &c. The form oh is the more usual in prose.—O hone! Och hone! an Irish exclamation of lamentation. [A.S. .]

  2. O

    usually written o', an abbrev. for of and on.

Dictionary of Nautical Terms

  1. o

    The fourth class of rating on Lloyd's books for the comparative excellence of merchant ships. But insured vessels are rarely so low. (See A.) O! OR HO! An interjection commanding attention or possibly the cessation of any action.

Suggested Resources

  1. o

    The o symbol -- In this Symbols.com article you will learn about the meaning of the o symbol and its characteristic.

  2. o

    Song lyrics by o -- Explore a large variety of song lyrics performed by o on the Lyrics.com website.

How to pronounce O?

  1. Alex
    US English

How to say O in sign language?


  1. Chaldean Numerology

    The numerical value of O in Chaldean Numerology is: 7

  2. Pythagorean Numerology

    The numerical value of O in Pythagorean Numerology is: 6

Images & Illustrations of O

  1. OOOOO

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Translations for O

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    an estate where cash crops are grown on a large scale (especially in tropical areas)
    • A. substitute
    • B. assault
    • C. plantation
    • D. bowel

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