Gr. toxikon = poisoned arrow, toxon = bow, and plasma = something molded

This genus of intracellular parasitic protozoa was named for its arc-like shape. Charles Nicolle and Louis Manceaux published the definitive description of the organism in 1909 after they observed the parasites in the blood, spleen, and liver of a North African rodent, Ctenodactylus gondii. The species T. gondii was formally designated at that time.