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urushiol

American  
[oo-roo-shee-awl, -ol] / ʊˈru ʃiˌɔl, -ˌɒl /

noun

  1. a toxic, liquid, catechol derivative, the active irritant principle in several species of the plant genus Rhus, as in poison ivy.


urushiol British  
/ uːˈruː-, ˈuːrʊʃɪˌɒl /

noun

  1. a poisonous pale yellow liquid occurring in poison ivy and the lacquer tree

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

urushiol Scientific  
/ -ro̅o̅shē-ôl′,-ōl′ /
  1. A toxic substance present in the resin or on the surface of plants of the genus Rhus (syn. Toxicodendron). Urushiol is a mixture of several derivatives of catechol and is the irritating substance in poison ivy.


Etymology

Origin of urushiol

1910–15; < Japanese urushi lacquer + -ol 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The oily substance it contains, urushiol, tends to cause more intense reactions over time and it affects up to 90 percent of people.

From National Geographic

Mango skin contains a chemical called urushiol, which can cause an allergic reaction similar to that of poison ivy in some people.

From Salon

After a bit of research, we were able to conclude that the reaction was caused by the urushiol oil on the skin of a mango!

From Scientific American

Mangos, cashews and pistachios can contain small amounts of urushiol.

From Scientific American

In the past, dermatologists believed that urushiol rashes and itch were triggered by the immune system's T cells, which rally antibodies to attack the skin irritant.

From Scientific American