Definition of rickettsia
rickettsiaeplay \-sē-ˌē, -ˌī\ also
: 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) ◆Rickettsia are often pleomorphic, and may be coccoid, rod-shaped, or irregularly-shaped.
rickettsialplay \-sē-əl\ adjective
Origin and Etymology of rickettsia
New Latin, genus name, from Howard T. Ricketts †1910 American pathologist
First Known Use: 1916
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)
Learn More about rickettsia
Britannica.com: Encyclopedia article about rickettsia
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