noun Ar·chaeo·cy·a·thus \-thəs\

Definition of Archaeocyathus

  1. :  a genus of Cambrian fossils with characteristics of both sponges and corals that is included among the pleosponges or placed in Archaeocyatha

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Origin and Etymology of archaeocyathus

New Latin, from archae- + Latin cyathus cup — more at cyathus

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a brief usually trivial fact

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