poison oak

noun

: a common bush in the western U.S. that causes a very itchy and painful rash on your skin if you touch it

Full Definition of POISON OAK

: any of several plants related to poison ivy and producing an oil with similar irritating properties: as

a : a bushy plant (Toxicodendron diversilobum syn. Rhus diversiloba) of the Pacific coast

b : a bushy plant (Toxicodendron toxicarium syn. Rhus toxicodendron) chiefly of the southeastern U.S.

: poison ivy 1a

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See poison oak defined for kids

First Known Use of POISON OAK

1743

Rhymes with POISON OAK

artichoke, at a stroke, Bolingbroke, chestnut oak, equivoque, fisherfolk, gentlefolk, go for broke, herrenvolk, hub-and-spoke, masterstroke, ministroke, monocoque, mourning cloak, okeydoke, Roanoke, thunderstroke, turkey oak, water oak, womenfolk

POISON OAK Defined for Kids

poison oak

noun

Definition of POISON OAK for Kids

: a bush related to poison ivy that can cause an itchy painful rash when touched

Medical Dictionary

poison oak

noun \-ˈōk\

Medical Definition of POISON OAK

: 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

: poison ivy 1a

: a skin rash produced by poison oak