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o

o

8 6.6
The fifteenth letter of the English alphabet, as in octopus
  • noun
  • /oʊ/
translation icon : o
  • In the word 'dog', the letter o comes after the letter 'd'.
  • o-lantern
  • o-potty
  • o-jack

Can you tell me the long and short sounds of the letter O?

Examples

  • - Righty-o!

  • The letter o is often used as a vowel in English words.

  • You start to let her know you are OK by giving her a big "O" over your head.

  • '11 o' clock.' - '11 o' clock, fine.' - 'Good idea.' - 'Alright, fine.'

  • Duck traced his index finger around the 'o' of HOLY on the front of the book next to him.

    Fiction book (1998)
  • And Bingo was his name-o.

  • Sing, O spirits!

    Fiction book (1991)
  • And you're the only state that starts with an O Except for Oklahoma and Ohio, you're the only state that starts with an OR.

  • Aaron Probst grew his hair out, then shaved and painted the O to be ready for the 2010 Stanford football game.

    Blog text (23)
  • ♪ Bingo was his name-o

Synonyms

O
vso
40 4.9

The fifteenth letter of the alphabet shaped like a circle

refers to the fifteenth letter specifically in the English 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

The letter o comes from an old round sign and still looks like a small circle. The Greeks called the small 'o' omicron ('o' + 'small') and the large 'o' omega ('o' + 'large'), so the letter's name and shape remind us of a round, open circle.