n., pl., -si·ae (-sē-ē').
Any of various bacteria of the genus Rickettsia, carried as parasites by many ticks, fleas, and lice, that cause diseases such as typhus, scrub typhus, and Rocky Mountain spotted fever in humans.
[New Latin Rickettsia, genus name, after Howard Taylor Ricketts (1871-1910), American pathologist.]
rickettsial rick·ett'si·al adj.
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
