acritarch

noun
ac·ri·tarch | \ ˈa-kri-ˌtärk \

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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Dictionary Entries near acritarch

acrimonious

acrimony

acrinyl

acritarch

acroama

acroamatic

acroamatics

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The first known use of acritarch was in 1963

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