nannoplankton

noun

nan·​no·​plank·​ton ˌna-nō-ˈplaŋ(k)-tən 

-ˌtän

: the smallest plankton that consists of those organisms (such as bacteria) passing through nets of very fine mesh silk cloth

Word History

Etymology

New Latin, from Greek nanos, nannos dwarf + New Latin plankton plankton

First Known Use

1912, in the meaning defined above