Medical Dictionary

poison oak

noun \-ˈōk\

Medical Definition of POISON OAK

1
:  any of several plants included in the genus Rhus or sometimes in the genus Toxicodendron that produce an irritating oil like that of poison ivy: a :  a bushy plant (R. diversiloba synonym T. diversilobum) of the Pacific coast b :  a bushy plant (R. toxicodendron synonym T. pubescens) of the southeastern United States
2
:  poison ivy 1a
3
:  a skin rash produced by poison oak

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