is a specific kind of: protoctist.

is a broader term that covers: sarcodine, sarcodinian | rhizopod, rhizopodan | arcella | difflugia | ciliate, ciliated protozoan, ciliophoran | euglena | flagellate, flagellate protozoan, flagellated protozoan, mastigophoran, mastigophore | plantlike flagellate | sporozoan.

has as a part: cytostome.

is a member of: phylum Protozoa, Protozoa.

derivation: protozoal, protozoan, protozoic.