noun
Uncommon
oo
OH-oh
Oo (noun) means the Greek letter omega (Ω, ω), sometimes written this way to show its long "o" sound. Example: “The physics formula used oo to represent angular velocity.”
noun
1
The Greek letter omega (Ω, ω), sometimes written this way to show its long "o" sound.
"The physics formula used oo to represent angular velocity."
2
Any of several now-extinct Hawaiian honeyeater-like birds of the genus Moho, prized historically for their yellow feathers.
"The last confirmed oo sighting was decades before the species was declared extinct."
How to use oo
Learner’s notesIn plain EnglishEither a way of writing the Greek letter omega, or an extinct Hawaiian bird once hunted for its feathers.
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Word forms
- Plural
- oos
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The physics formula used _____ to represent angular velocity.
Etymology
The bird sense comes from Hawaiian ʻōʻō, imitating the bird's call; the letter sense is simply a spelled-out way of writing the long "o" sound of omega.
Synonyms
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omega
o-o
Related words
Rhymes for oo
See all rhymes for oo →Frequently asked questions
What does “oo” mean?
The word “oo” means the Greek letter omega (Ω, ω), sometimes written this way to show its long "o" sound. In plain terms, either a way of writing the Greek letter omega, or an extinct Hawaiian bird once hunted for its feathers.
How do you pronounce “oo”?
“Oo” is pronounced OH-oh (/ˈoʊ.oʊ/ in IPA).
How do you use “oo” in a sentence?
Here is “oo” used in a sentence: “The physics formula used oo to represent angular velocity.”
What part of speech is “oo”?
“Oo” is a noun.
Is “oo” a common word?
“Oo” is an uncommon word in modern English.
How many meanings does “oo” have?
“Oo” has 2 distinct senses listed in this dictionary. The most common is: the Greek letter omega (Ω, ω), sometimes written this way to show its long "o" sound.
What does "oo" mean when referring to a letter?
"Oo" can refer to the Greek letter omega (Ω, ω), written this way in transliteration to represent its long "o" sound. It appears in linguistic or academic texts discussing Greek phonetics.
What is the "oo" bird?
The oo (or ʻōʻō) refers to any of several now-extinct Hawaiian honeyeater-like birds of the genus Moho. These birds were historically prized for their yellow feathers, which were used in Hawaiian featherwork.
Why are the oo birds extinct?
All known species of oo in the genus Moho are now extinct, following historical hunting for their prized yellow feathers along with broader environmental pressures on Hawaiian bird populations. None survive today.
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