adradius

noun

ad·​ra·​di·​us

(ˈ)ad-ˈrā-dē-əs

plural adradii

(ˈ)ad-ˈrā-dē-ˌī

or adradiuses

: a radius of the third order in coelenterates

Word History

Etymology

ad- + radius

First Known Use

1888, in the meaning defined above

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