Definition of phytoplankter in US English:
phytoplankter
noun
Biology
An individual or species of the phytoplankton; a planktonic plant.
Origin
1930s; earliest use found in Ecological Monographs. From phyto- + plankter, after phytoplankton.
Pronunciation
phytoplankter
/ˈfʌɪtəʊˌplaŋ(k)tə/