Definition of o
(Entry 1 of 11)
1a
: the 15th letter of the English alphabet
b
: a graphic representation of this letter
c
: a speech counterpart of orthographic o
2
: a graphic device for reproducing the letter o
3
: one designated o especially as the 15th in order or class
Definition of o (Entry 2 of 11)
1
ocean
2
ohm
3
old
4
order
5
over
less common spelling of oh
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
—used in direct address oh, waiter! Will you come here, please?
3
—used to express acknowledgment or understanding of a statement Oh, yes. It's one of my favorite cities.
4
—used to introduce an example or approximation Their house is about, oh, I'd say four miles from here.
O
noun (2)Definition of O (Entry 4 of 11)
: 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
Definition of O (Entry 5 of 11)
1
offense
2
Ohio
3
[New Latin octarius]
pint
O
symbolDefinition of O (Entry 6 of 11)
oxygen
variants:
or oo-
Definition of o- (Entry 7 of 11)
: egg
oology
specifically
: ovum
oogonium
Definition of o- (Entry 8 of 11)
orth- or ortho-
-o-
affixDefinition of -o- (Entry 9 of 11)
—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 speedometerelastomer
-o
noun suffixDefinition of -o (Entry 10 of 11)
: one that is, has the qualities of, or is associated with
bucko
-o
interjection suffixDefinition of -o (Entry 11 of 11)
—in interjections formed from other parts of speech cheeriorighto
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Merriam-Webster unabridged
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Time Traveler for o
The first known use of o was before the 12th century
See more words from the same century