poison oak

poison oak


: 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

First Known Use of POISON OAK


poison oak

noun \-ˈōk\   (Medical Dictionary)

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
: a skin rash produced by poison oak

poison oak

noun    (Concise Encyclopedia)

Species of poison ivy (Toxicodendron diversilobum) native to western North America and classified in the sumac (or cashew) family. Like many other lobe-leafed plants commonly called oak, poison oak is not an oak tree (genus Quercus).


Next Word in the Dictionary: poisonous
Previous Word in the Dictionary: poison nut
All Words Near: poison oak

Seen & Heard

What made you want to look up poison oak? Please tell us where you read or heard it (including the quote, if possible).

Get Our Free Apps
Voice Search, Favorites,
Word of the Day, and More
Join Us on FB & Twitter
Get the Word of the Day and More