Pfiesteria
noun
Pfie·ster·ia
| \ fē-ˈstir-ē-ə
, fis-ˈtir-
\
, fis-ˈtir-
\
Medical Definition of Pfiesteria
: a genus of dinoflagellates including one (Pfiesteria piscicida) found in waters especially along the middle and southern Atlantic coast of the United States that produces a toxin which causes skin lesions in fish, that feeds upon the lesions sometimes causing large fish die-offs, and that may cause symptoms (as skin lesions and memory loss) in humans exposed to the toxin