rickettsia

noun rick·ett·sia \ ri-ˈket-sē-ə \
Updated on: 15 Nov 2017

Definition of rickettsia

plural rickettsias or rickettsiae play \ri-ˈket-sē-ˌē, -ˌī\ also rickettsia
: any of a various gram-negative, parasitic bacteria (order Rickettsiales and especially genus Rickettsia) that are transmitted by biting arthropods (such as lice or ticks) and cause a number of serious diseases (such as Rocky Mountain spotted fever and typhus)
Note: Rickettsia are often pleomorphic, and may be coccoid, rod-shaped, or irregularly-shaped.

rickettsial

play \ri-ˈket-sē-əl\ adjective

Origin and Etymology of rickettsia

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


Medical Dictionary

rickettsia

noun rick·ett·sia \ ri-ˈket-sē-ə \

medical Definition of rickettsia

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

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