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O

O

40 4.9
The fifteenth letter of the alphabet shaped like a circle
  • noun
  • /oʊ/
translation icon : o
  • A minus on O is just zero.

And so just ask yourself why the O in mom stands for observation.

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Examples

  • In the alphabet, O comes after N and before P.

  • Starts with a "W", "O" in the middle, "D" at the end.

  • And so just ask yourself why the O in mom stands for observation.

  • The mouths of the first group of people formed an O, and their eyes glittered with admiration.

    Blog text (27)
  • Slides his finger through the O created by his thumb and forefinger. Team (cont'd)

    Fiction book (2001)
  • The letter O is often used as a grade in academic settings.

  • The word 'octopus' starts with the letter O.

Synonyms

o
vsO
8 6.6

The fifteenth letter of the English alphabet, as in octopus

is the fifteenth letter in the Roman alphabet

Idioms

uh-oh, Spaghetti-O
  • Baby Talk
9.9

A short phrase showing mild surprise or worry said in a playful way

Compounds

group O
  • Specialized
47 3.7

A blood type with no A or B markers that can be given to most people

46 2.8

A sweet, fruit flavored dessert made from a powder that becomes soft and wobbly

type O
  • Specialized
7 3.9

A blood group whose red cells have no A or B markers, so they can donate to anyone

O-ring
  • Specialized
1 6.1

A round rubber or plastic ring that seals a joint to stop leaks

O level
  • Archaic
1 7.9

A public exam in the UK for secondary students, now replaced by GCSEs

jack-o-lantern
  • Specialized
9.9

A large poisonous mushroom with an orange cap that glows at night

A large poisonous mushroom with orange caps that grows in tight groups and gills that glow in the dark

9.9

A state of becoming very jumpy and worried when stressed

penicillin O
  • Specialized
4.6

A medicine made by some mould that kills bacteria and is like penicillin G

A way to make people smell scents while watching films or TV

Surface Forms

O singular
Os plural

Etymology

O comes from a very old sign called ayin that meant 'eye' and looked like a round eye. That's why O is a round shape and is the fifteenth letter of our alphabet.