poison oak


Definition of poison oak

1 : any of several plants related to poison ivy and producing an oil with similar irritating properties: such as
a : a bushy plant (Toxicodendron diversilobum synonym Rhus diversiloba) of the Pacific coast
b : a bushy plant (Toxicodendron toxicarium synonym Rhus toxicodendron) chiefly of the southeastern U.S.

Examples of poison oak in a Sentence

Recent Examples on the Web Hardeman sprayed Roundup on weeds at his home in Gualala and later on poison oak at his 56-acre property in Santa Rosa. Bob Egelko, San Francisco Chronicle, 24 Nov. 2021 Indigenous people made an herbal tea from its leaves and berries to treat poison oak rash, bronchitis, and stomach and kidney ailments. Brian E. Clark, Los Angeles Times, 30 Sep. 2021 While the sheep excel at mowing grass, the goats are experts at trimming lower tree branches and thinning poison oak, coyote brush and brambles. Tara Duggan, San Francisco Chronicle, 26 July 2021 Alternatively, contact a professional poison ivy/poison oak removal service. oregonlive, 20 June 2021 So, poison ivy, poison oak, and poison sumac all cause irritation to the skin through a plant oil—technically called urushiol oil—found in the sap of these plants, according to the US Food & Drug Administration (FDA). Maggie O'neill, Health.com, 14 May 2021 Hardeman, now 72, sprayed Roundup on weeds at his home in Gualala and later on poison oak at his 56-acre property in Santa Rosa. Bob Egelko, San Francisco Chronicle, 14 May 2021 Going off trail in the grasslands not only disturbs the homes of wildlife but also puts visitors at risk for snake bites, ticks and poison oak. San Diego Union-Tribune, 13 May 2021 From being on the watch for rattlesnakes and mountain lions, to numerous bouts with poison oak, Garza has had a lot to learn about rural life. Samantha Nobles-block, SFChronicle.com, 22 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'poison oak.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of poison oak

1739, in the meaning defined at sense 1

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Time Traveler for poison oak

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The first known use of poison oak was in 1739

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Dictionary Entries Near poison oak

poison nut

poison oak


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Statistics for poison oak

Last Updated

29 Nov 2021

Cite this Entry

“Poison oak.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/poison%20oak. Accessed 8 Dec. 2021.

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More Definitions for poison oak

poison oak


English Language Learners Definition of 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

poison oak


Kids Definition of poison oak

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

poison oak

\ -ˈōk How to pronounce poison oak (audio) \

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
3 : a skin rash produced by poison oak

More from Merriam-Webster on poison oak

Britannica.com: Encyclopedia article about poison oak


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