acritarch
noun
ac·ri·tarch
ˈa-kri-ˌtärk 
: 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
Cite this Entry
“Acritarch.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acritarch. Accessed 3 Nov. 2025.
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