plural noun Cyr·toi·dae \sərˈtȯi(ˌ)dē\

Definition of Cyrtoidae

  1. :  a family of radiolarians widely distributed and often employed as a paleontological index group — compare index fossil

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Origin and Etymology of cyrtoidae

New Latin, from cyrt- + -idae

Seen and Heard

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feeling or affected by lethargy

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