Medical Definition of colonize
transitive verb: to establish a colony in or on <the parasitic roundworms…have succeeded in colonizing a great variety of hosts—W. H. Dowdeswell>
2: to isolate in supervised groups
intransitive verbof microorganisms : to become established in a habitat (as a host or a wound) <these bacteria in turn colonize in other parts of the body—R. A. Runnells>
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