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acritarch

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noun ac·ri·tarch \ˈa-kri-ˌtärk\

Definition of acritarch

  1. :  any of a group of fossil one-celled marine planktonic organisms of uncertain and possibly various taxonomic affinities held to represent the earliest known eukaryotes



Origin of acritarch

Greek akritos uncertain (from a- + kritos, verbal of krinein to decide) + archē beginning — more at certain, arch-


First Known Use: 1963


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