- Rickettsia - any of a group of parasitic bacteria that live in arthropods (as ticks and mites) and can cause disease if transmitted to human beings
--1 is a kind of eubacteria, eubacterium, true bacteria; bacteria, bacterium; eubacteria, eubacterium, true bacteria; bacteria, bacterium
--1 is a member of Rickettsiaceae, family Rickettsiaceae