oo-

¹ American  

1. a combining form meaning “egg,” used in the formation of compound words.

   oogamous.

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o'o ² American  

[oh-oh] / ˈoʊ oʊ /

Or 'ō'ō

noun

plural

o’os

1. any of several species of Hawaiian birds of the extinct genus Moho, especially the extinct M. nobilis (Hawaiian o'o ), which had black plumage and two tufts of yellow plumes used to make ceremonial robes for the Hawaiian kings. The last surviving species was M. braccatus (Kauai o'o ), classified as extinct in 1987.

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oo- British  

combining form

1. egg or ovum

   oosperm

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Usage

What does oo- mean? Oo- is a combining form used like a prefix meaning “egg.” It is used in many scientific terms, especially in biology.Oo- comes from the Greek ōión, meaning “egg.” The Greek ōión helps form the word ōophóros, meaning “egg-bearing” and is the source of the combining form oophoro-, used to indicate the ovary.Distantly related to the Greek ōión is the Latin word for egg, ōvum, source of the related combining forms ov-, ovi-, and ovo-, also used to mean “egg.” The Latin ōvum is ultimately the origin of ovario-, used, like oophoro-, to mean “ovary.”What are variants of oo-?When combined with words or word elements that begin with a vowel, oo- becomes o-, as in oidium.

Etymology

Origin of oo-¹

< Greek ōio-, combining form of ōión egg ¹

Origin of o'o²

First recorded in 1885–90; from Hawaiian ʿōʿō