nannofossilPronunciation: /ˈnanəʊˌfɒs(ə)l, -sɪl/ (also nanofossil)Definition of nannofossil noun the fossil of a minute planktonic organism, especially a calcareous unicellular alga. Origin: 1960s: from nannoplankton (variant of nanoplankton) + fossilnannofossil in other Oxford dictionaries Definition of nannofossil in the US English dictionary
