uru·​shi·​ol yu̇-ˈrü-shē-ˌȯl How to pronounce urushiol (audio)
-ˌōl How to pronounce urushiol (audio)
: a mixture of catechol derivatives with saturated or unsaturated side chains of 15 or 17 carbon atoms that is an oily toxic irritant substance present in poison ivy and some related plants (such as poison oak and poison sumac)

Examples of urushiol in a Sentence

Recent Examples on the Web Because urushiol can cling to clothing and shoes, take precautions not to transfer the oily substance to yourself or other items when undressing. Christopher Bergland, Verywell Health, 3 July 2024 For example, mango skin contains urushiol, the same compound found in poison ivy, which can trigger allergic reactions in people who are susceptible. Nick Blackmer, Verywell Health, 12 June 2024 This is because every part of the plant contains and emits a resin known as urushiol. Southern Living Editors, Southern Living, 29 July 2023 Mangos, cashews and pistachios can contain small amounts of urushiol. Scientific American, 1 Jan. 2022 People who are highly allergic to urushiol can even develop a skin rash just by being exposed to the smoke. Brittany Anas, House Beautiful, 28 June 2023 The severity also depends on the amount of urushiol that gets on your skin, the Mayo Clinic notes. Christopher Kuhagen, Journal Sentinel, 6 June 2023 Source of irritation All parts of poison ivy contain an oily compound called urushiol. Mike Hogan, The Enquirer, 28 May 2023 Dish soap is made to handle grease and oil and can help treat urushiol. Jim Cobb, Field & Stream, 10 May 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'urushiol.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


International Scientific Vocabulary, from Japanese urushi lacquer + International Scientific Vocabulary -ol entry 1

First Known Use

1908, in the meaning defined above

Time Traveler
The first known use of urushiol was in 1908

Dictionary Entries Near urushiol

Cite this Entry

“Urushiol.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/urushiol. Accessed 24 Jul. 2024.

Medical Definition


uru·​shi·​ol (y)u̇-ˈrü-shē-ˌȯl How to pronounce urushiol (audio) -ˌōl How to pronounce urushiol (audio)
: a mixture of pyrocatechol derivatives with saturated or unsaturated side chains of 15 or 17 carbon atoms that is an oily toxic irritant principle present in poison ivy and some related plants of the genus Rhus

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