Kalmar "flagellate protozoan" tana nufin wani nau'in halitta mai sel guda ɗaya (protozoan) wanda ke motsawa ta hanyar tsari ɗaya ko fiye kamar bulala da ake kira flagella. Wadannan kwayoyin halitta ana siffanta su da yadda suke iya tafiya da sauri ta cikin ruwa ko wasu ruwaye, ta hanyar amfani da tutarsu don ciyar da kansu gaba. Wasu misalan protozoans na flagellate sun haɗa da Euglena, Trypanosoma, da Giardia, da sauransu.Da yawa flagellate protozoans sune mahimman sassan halittun ruwa, suna zama tushen abinci ga sauran halittu. Duk da haka, wasu nau'ikan na iya haifar da cututtuka a cikin mutane da dabbobi, suna mai da su mahimman manufa don binciken likita da dabbobi.