atto-

combining form at·to- \ˈa-(ˌ)tō\

Definition of atto-

  1. :  one quintillionth (10−18) part of attogram

Origin and Etymology of atto-

International Scientific Vocabulary, from Danish or Norwegian atten eighteen, from Old Norse āttjān; akin to Old English eahtatīene eighteen


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not embarrassed or apologetic

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