立克次體 lìkècìtǐ rickettsia Origin Definitions Defs Strokes Stroke Words Sentences Sents 普氏立克次体 pǔshìlìkècìtǐ Rickettsia prowazekii Rickettsia prowazekii; a species of bacteria that is the causative agent of epidemic typhus立氏立克次体 lìshìlìkècìtǐ Rickettsia rickettsii A species of bacterium that causes Rocky Mountain spotted fever in humans