acritarch

[ ak-ri-tahrk ]

noun

, Paleontology.

1. any of various microfossils, of unknown biological affinities, having a central cavity enclosed by a wall of chiefly organic composition.

Other Words From

• acri·tarchous adjective

Word History and Origins

Origin of acritarch¹

1963; < New Latin Acritarcha (neuter plural), irregular < Greek ákrit ( os ) confused, doubtful ( a- ⁶, critic ) + archḗ beginning, origin ( archi- )