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rickettsia

play
noun rick·ett·sia \ri-ˈket-sē-ə\

Definition of rickettsia

plural rick·ett·si·as or rick·ett·si·aeplay \-sē-ˌē, -ˌī\ also rick·ett·sia

  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)

rick·ett·si·al 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 :  the type genus of the family Rickettsiaceae comprising rod-shaped, coccoid, or diplococcus-shaped often pleomorphic bacteria that live intracellularly in biting arthropods (as lice or ticks) and when transmitted to humans by the bite of an arthropod host cause a number of serious diseases (as Rocky Mountain spotted fever and typhus)

  2. 2plural rick·ett·si·ae \-ˌē\play also rick·ett·sias or rick·ett·sia :  any bacterium of the order Rickettsiales and especially of the family Rickettsiaceae




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