ac·​ri·​tarch | \ ˈa-kri-ˌtärk How to pronounce acritarch (audio) \

Definition of acritarch

: 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

First Known Use of acritarch

1963, in the meaning defined above

History and Etymology for acritarch

Greek ákritos "confused, uncertain" (from a- a- entry 2 + kritós, verbal adjective of krī́nein "to separate, decide") + archḗ "beginning" — more at certain entry 1, arch- entry 1

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The first known use of acritarch was in 1963

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Cite this Entry

“Acritarch.” Dictionary, Merriam-Webster, Accessed 13 May. 2021.

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