Definition of poison oak
1 : any of several plants related to poison ivy and producing an oil with similar irritating properties: such asa : a bushy plant (Toxicodendron diversilobum synonym Rhus diversiloba) of the Pacific coastb : a bushy plant (Toxicodendron toxicarium synonym Rhus toxicodendron) chiefly of the southeastern U.S.
2 : poison ivy 1a
First Known Use of poison oak
POISON OAK Defined for English Language Learners
Definition of poison oak for English Language Learners
: a common bush in the western U.S. that causes a very itchy and painful rash on your skin if you touch it
POISON OAK Defined for Kids
Definition of poison oak for Students
: a bush related to poison ivy that can cause an itchy painful rash when touched
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 coastb: 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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