O, o

[oh] /oʊ/
noun, plural O's or Os; o's or os or oes.
1.
the fifteenth letter of the English alphabet, a vowel.
2.
any spoken sound represented by the letter O or o, as in box, note, short, or love .
3.
something having the shape of an O .
4.
a written or printed representation of the letter O or o.
5.
a device, as a printer's type, for reproducing the letter O or o.

O

[oh] /oʊ/
interjection
1.
(used before a name in direct address, especially in solemn or poetic language, to lend earnestness to an appeal):
Hear, O Israel!
2.
(used as an expression of surprise, pain, annoyance, longing, gladness, etc.)
noun, plural O's.
3.
the exclamation “O.”.
Origin
1125-75; Middle English < Old French < Latin ō

O

1.
Old.
2.
Grammar, object.

O

Symbol.
1.
the fifteenth in order or in a series.
2.
the Arabic cipher; zero.
3.
(sometimes lowercase) the medieval Roman numeral for 11.
Compare Roman numerals.
4.
Physiology. a major blood group, usually enabling a person whose blood is of this type to donate blood to persons of group O, A, B, or AB and to receive blood from persons of group O.
Compare ABO system.
5.
Chemistry, oxygen.
6.

o'

[uh, oh] /ə, oʊ/
preposition
1.
an abbreviated form of of, as in o'clock or will-o'-the-wisp.
2.
an abbreviated form of on.
Origin
Middle English; by shortening.

O'

1.
a prefix meaning “descendant,” in Irish family names:
O'Brien; O'Connor.
Origin
representing Irish ó descendant, Old Irish au

o-1

Chemistry
1.
an abridgment of ortho-.

o-2

1.
variant of ob- before m:
omission.

o-3

1.
variant of oo-:
oidium.

-o-

1.
the typical ending of the first element of compounds of Greek origin (as -i-, is, in compounds of Latin origin), used regularly in forming new compounds with elements of Greek origin and often used in English as a connective irrespective of etymology:
Franco-Italian; geography; seriocomic; speedometer.
Compare -i-.
Origin
Middle English (< Old French) < Latin < Greek

-o

1.
a suffix occurring as the final element in informal shortenings of nouns (ammo; combo; condo; limo; promo); -o, also forms nouns, usually derogatory, for persons or things exemplifying or associated with that specified by the base noun or adjective (cheapo; pinko; sicko; weirdo; wino).
2.
a suffix occurring in colloquial noun or adjective derivatives, usually grammatically isolated, as in address:
cheerio; kiddo; neato; righto.
Origin
perhaps orig. the interjection O, appended to words as in def 2; as a derivational suffix reinforced by clipped forms of words with -o- as a linking element (e.g., photo, stereo), by Rom nouns ending in o, and by personal nouns such as bimbo and bozo, of obscure origin

O.1

1.
(in prescriptions) a pint.
Origin
< Latin octārius

O.2

1.
2.
3.
4.
Ohio.
5.
Old.
6.
7.

o.1

1.
pint.
Origin
< Latin octārius

o.2

1.
2.
off.
3.
old.
4.
only.
5.
6.
Baseball. out; outs.

omicron

[om-i-kron, oh-mi-] /ˈɒm ɪˌkrɒn, ˈoʊ mɪ-/
noun
1.
the 15th letter of the Greek alphabet (O, o).
2.
the vowel sound represented by this letter.
Origin
< Greek ō mikrón, literally, small o. Cf. omega
Examples from the web for o
  • The intensification of the difference between rounded and unrounded e and o.
  • The predominant letter in the ending forms of this declension is o.
  • When the meaning of the name was no longer understood, it lost its prefix o.
  • The point of intersection, where the axes meet, is called the origin normally labeled o.
British Dictionary definitions for o

o

/əʊ/
noun (pl) o's, O's, Os
1.
the 15th letter and fourth vowel of the modern English alphabet
2.
any of several speech sounds represented by this letter, in English as in code, pot, cow, move, or form
3.
another name for nought

O1

symbol
1.
(chem) oxygen
2.
a human blood type of the ABO group See universal donor
3.
(logic) a particular negative categorial proposition, such as some men are not married: often symbolized as SoP Compare A, E, I2
abbreviation
4.
(Austral, slang) offence
Word Origin
(for sense 3) from Latin (neg)o I deny

O2

/əʊ/
interjection
1.
a variant spelling of oh
2.
an exclamation introducing an invocation, entreaty, wish, etc: O God!, O for the wings of a dove!

o-

prefix
1.
short for ortho- (sense 4)

o'

/ə/
preposition
1.
(informal or archaic) shortened form of of a cup o' tea

-o

suffix
1.
forming informal and slang variants and abbreviations, esp of nouns: wino, lie doggo, Jacko
Word Origin
probably special use of oh

-o-

connective vowel
1.
used to connect elements in a compound word: chromosome, filmography Compare -i-
Word Origin
from Greek, stem vowel of many nouns and adjectives in combination

omicron

/əʊˈmaɪkrɒn; ˈɒmɪkrɒn/
noun
1.
the 15th letter in the Greek alphabet (Ο, ο), a short vowel, transliterated as o
Word Origin
from Greek ō mikron small o; see micro-, omega
Word Origin and History for o

interjection of fear, surprise, admiration, etc.; see oh.

O

blood type, 1926, originally "zero," denoting absence of A and B agglutinogens.

O'

as a prefix in Irish names, from Irish ó, ua (Old Irish au) "descendant."

omicron

15th letter of the Greek alphabet, literally "small 'o,' " from Greek (s)mikros "small," from PIE *smik-. Because the vowel was "short" in ancient Greek. Cf. Omega.

o in Medicine

o
The Greek letter omicron. Entries beginning with this character are alphabetized under omicron.

O 1

The symbol for the element oxygen.

O 2
abbr.
oculus

o- abbr.
ortho- (often italic)

-o-
Used as a connective to join word elements: acidophilic.

omicron om·i·cron (ŏm'ĭ-krŏn', ō'mĭ-)
n.

Symbol o The 15th letter of the Greek alphabet.

o in Science
O  
The symbol for oxygen.
oxygen
  (ŏk'sĭ-jən)   
Symbol O
A nonmetallic element that exists in its free form as a colorless, odorless gas and makes up about 21 percent of the Earth's atmosphere. It is the most abundant element in the Earth's crust and occurs in many compounds, including water, carbon dioxide, and iron ore. Oxygen combines with most elements, is required for combustion, and is essential for life in most organisms. Atomic number 8; atomic weight 15.9994; melting point -218.4°C; boiling point -183.0°C; gas density at 0°C 1.429 grams per liter; valence 2. See Periodic Table.

Our Living Language  : In 1786, the French chemist Antoine Lavoisier coined a term for the element oxygen (oxygène in French). He used Greek words for the coinage: oxy- means "sharp," and -gen means "producing." Oxygen was called the "sharp-producing" element because it was thought to be essential for making acids. Lavoisier also coined the name of the element hydrogen, the "water-producing" element, in 1788. Soon after, in 1791, another French chemist, J. A. Chaptal, introduced the word nitrogen, the "niter-producing" element, referring to its discovery from an analysis of nitric acid.
Slang definitions & phrases for o

-o

suffix
  1. used to form adjectives
  2. Having the indicated characteristics: berserko/ luxo/ neato/ sicko/ wrongo
  3. used to form nouns 2: foldo/ freako/ klutzo/ muso •This fanciful formation is increasingly current
Related Terms

double-o, five-o, four-o, single-o

[1960s+; fr a humorous imitation of Spanish or Italian words, more probably Spanish because of the similar el -o pattern of coinage]


o in Technology

character
ASCII code 79, The letter of the alphabet, not to be confused with 0 (zero) the digit.
(1999-02-07)

Related Abbreviations for o

o

  1. Latin octarius (pint)
  2. octavo
  3. ohm

O

  1. old
  2. Oriental (as in personal ads, but usually A, Asian)
  3. out
  4. outstanding

O.

  1. ocean
  2. Ohio