Medical Definition of Plerocercoid
1. A stage in the development of a tapeworm following the procercoid stage, which develops in an animal serving as the second or subsequent intermediate host; a wormlike nonsegmented larva with an invaginated scolex at one end, usually unencysted in the flesh of various fishes, reptiles, or amphibians, the ingestion of which transmits the parasite to the final host. See: Diphyllobothrium latum. Origin: G. Pleres, full, complete, + kerkos, tail (05 Mar 2000)