Home › Words › G › gregarinegregarinegregarine means any of various sporozoan protozoans (subclass Gregarinasina) that are parasitic in the digestive tracts of some invertebrates.EtymologyFrom Latin gregārius (“herd-like”).nounAny of various sporozoan protozoans (subclass Gregarinasina) that are parasitic in the digestive tracts of some invertebrates.Definitions & examples from Wiktionary (CC BY-SA 3.0).