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rickettsia

play
noun, rick·ett·sia \ri-ˈket-sē-ə\

Definition of rickettsia

plural rickettsias or rickettsiaeplay \-sē-ˌē, -ˌī\ also rickettsia

  1. :  any of a family (Rickettsiaceae) of rod-shaped, coccoid, or diplococcus-shaped, often pleomorphic gram-negative bacteria that are intracellular parasites of arthropods (as lice or ticks) and when transmitted to humans cause various diseases (as typhus)

rickettsial play \-sē-əl\ adjective


Origin of rickettsia

New Latin, genus name, from Howard T. Ricketts †1910 American pathologist


First Known Use: 1919


Medical Dictionary

rickettsia

play
noun rick·ett·sia \ri-ˈket-sē-ə\

Medical Definition of rickettsia

  1. 1 capitalized :  a genus of rod-shaped, coccoid, or diplococcus-shaped often pleomorphic bacteria (family Rickettsiaceae) that are transmitted by biting arthropods (as lice or ticks) and cause a number of serious diseases (as Rocky Mountain spotted fever and typhus)

  2. 2plural rickettsiae \-ˌē\play also rickettsias or rickettsia :  any bacterium of the genus Rickettsia, the family Rickettsiaceae, or the order Rickettsiales




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