Actinosphaerium

noun

Ac·​ti·​no·​sphae·​ri·​um

¦ak-tə-(ˌ)nō-ˈsfir-ē-əm

: a genus of large freshwater protozoans (order Heliozoa)

Word History

Etymology

New Latin, from actin- + Greek sphairion little ball, diminutive of sphaira ball, sphere

First Known Use

1879, in the meaning defined above

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