from the GNU version of the Collaborative International Dictionary of English
- n.pl. An order of Protozoa, allied to the Rhizopoda, and parasitic in other animals, as in the earthworm, lobster, etc. When adult, they have a small, wormlike body inclosing a nucleus, but without external organs; in one of the young stages, they are amœbiform; -- called also Gregarinida, and Gregarinaria.
Sorry, no etymologies found.
We know to-day of a great number of these little beings, such as the gregarinae, flagellata, acineta, infusoria, etc.