(redirected from Tetrahydrourushiol)
Also found in: Medical.


 (o͝o-ro͞o′shē-ôl′, -ōl′, -ŏl′)
An oily, toxic substance composed of phenolic compounds that is present in the sap of various plants of the family Anacardiaceae and especially the genus Toxicodendron, including poison ivy, poison sumac, and the lacquer tree.

[Japanese urushi, lacquer + -ol.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈuːrʊʃɪˌɒl; uːˈruː-)
(Elements & Compounds) a poisonous pale yellow liquid occurring in poison ivy and the lacquer tree
[from Japanese urushi lacquer + -ol2]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ʊˈru ʃiˌɔl, -ˌɒl)

a catechol derivative that is the irritant in poison ivy and its allies.
[1910–15; < Japanese urushi lacquer]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
Mentioned in ?