urushiol

 
Pronunciation: /ʊˈruːʃɪɒl/

noun

[mass noun] Biochemistry
  • an oily liquid which is the main constituent of Japanese lacquer and is responsible for the irritant properties of poison ivy and other plants. It consists of a mixture of catechol derivatives.

Origin:

early 20th century: from Japanese urushi 'Japanese lacquer' + -ol