acritarch

acritarch
acritarchous, adj.
/ak"ri tahrk'/, n. Paleontol.
any of various microfossils, of unknown biological affinities, having a central cavity enclosed by a wall of chiefly organic composition.
[1963; < NL Acritarcha (neut. pl.), irreg. < Gk ákrit(os) confused, doubtful (see A-6, CRITIC) + arché beginning, origin (cf. ARCHI-)]

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Universalium. 2010.

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