[ ri-ket-see-uh ]
/ rɪˈkɛt si ə /
noun, plural rick·ett·si·ae [ri-ket-see-ee] /rɪˈkɛt siˌi/, rick·ett·si·as [ri-ket-see-uh z] /rɪˈkɛt si əz/.
any member of the genus Rickettsia, comprising rod-shaped to coccoid microorganisms that resemble bacteria but can be as small as a large virus and reproduce only inside a living cell, parasitic in fleas, ticks, lice, and mites and transmitted by bite to vertebrate hosts, including humans, causing such severe diseases as typhus and Rocky Mountain spotted fever.
any rickettsia or rickettsialike microorganism of the orders Rickettsiales and Chlamydiales.
Words nearby rickettsia
Origin of rickettsia
1915–20; < New Latin, after Howard T. Ricketts (1871–1910), U.S. pathologist; see -ia
OTHER WORDS FROM rickettsiarick·ett·si·al, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for rickettsia
/ (rɪˈkɛtsɪə) /
noun plural -siae (-sɪˌiː) or -sias
any of a group of parasitic bacteria that live in the tissues of ticks, mites, and other arthropods, and cause disease when transmitted to man and other animals
Derived forms of rickettsiarickettsial, adjective
Word Origin for rickettsia
C20: named after Howard T. Ricketts (1871–1910), US pathologist
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medicine definitions for rickettsia
[ rĭ-kĕt′sē-ə ]
A genus of gram-negative bacteria that are carried as parasites by many ticks, fleas, and lice and cause diseases such as typhus, scrub typhus, and Rocky Mountain spotted fever.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.