1

o

play
noun, often capitalized, often attributive \ˈō\

Definition of o

plural

o's

or

os

play \ˈōz\
  1. 1a :  the 15th letter of the English alphabetb :  a graphic representation of this letterc :  a speech counterpart of orthographic o

  2. 2 :  a graphic device for reproducing the letter o

  3. 3 :  one designated o especially as the 15th in order or class

  4. 4 :  something shaped like the letter O; especially :  zero

Examples of o in a Sentence

  1. a word that starts with an o

  2. a word that starts with o

Before 12th Century

First Known Use of o

before 12th century

Other Alphabet Terms


2

o

abbreviation

Definition of o

  1. 1 ocean

  2. 2 ohm

  3. 3 old

  4. 4 order

  5. 5 over


1

O

interjection

less common spelling of

  1. 1 —used to express an emotion (such as surprise or desire) or in response to physical stimuli Oh, no! I forgot my key. Oh, don't stop!

  2. 2 —used in direct address oh, waiter! Will you come here, please?

  3. 3 —used to express acknowledgment or understanding of a statement Oh, yes. It's one of my favorite cities.

  4. 4 —used to introduce an example or approximation Their house is about, oh, I'd say four miles from here.


2

O

play
noun \ˈō\

Definition of O

  1. :  the one of the four ABO blood groups characterized by the absence of antigens designated by the letters A and B and by the presence of antibodies against these antigens

1929

First Known Use of o

1929


3

O

abbreviation

Definition of O

  1. 1 offense

  2. 2 Ohio

  3. 3 [New Latin octarius] pint


4

O

symbol

Definition of O

  1. oxygen


1

o-

combining form
variants: or

oo-

Definition of o-

  1. :  egg oology; specifically :  ovum oogonium

Origin and Etymology of o-

Greek ōi-, ōio-, from ōion — more at egg


2

o-

abbreviation

Definition of o-

  1. orth- or ortho-


-o-

Definition of -o-

  1. —used as a connective vowel originally to join word elements of Greek origin and now also to join word elements of Latin or other origin speedometer elastomer

Origin and Etymology of -o-

Greek, thematic vowel of many nouns and adjectives in combination


1

-o

noun suffix

Definition of -o

  1. :  one that is, has the qualities of, or is associated with bucko

Origin and Etymology of -o

perhaps from 1oh


2

-o

interjection suffix

Definition of -o

  1. —in interjections formed from other parts of speech cheerio righto

Origin and Etymology of -o

probably from 1oh



O Defined for English Language Learners

noun

Definition of o for English Language Learners

  • : the 15th letter of the English alphabet

  • : the number zero

  • —used as a mark at the end of a letter, an e-mail, etc., to represent a hug


O Defined for Kids

o

noun , often cap \ˈō\

Definition of o for Students

plural

o's

or

os

\ˈōz\
  1. 1 :  the 15th letter of the English alphabet

  2. 2 :  zero 1


O

Definition of O for Students

  1. variant of oh


Medical Dictionary

noun \ˈō\

Medical Definition of O

  1. :  the one of the four ABO blood groups characterized by the absence of antigens designated by the letters A and B and by the presence of antibodies against these antigens


O

abbreviation

Medical Definition of O

  1. 1opening

  2. 2[Latin octarius] pint—used in writing prescriptions


O

symbol

Medical Definition of O

  1. oxygen


Learn More about o


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