: a toxic crystalline compound of arsenic C2H7AsO2 used especially as an herbicide
Word History
Etymology
German Kakodyl, the radical (CH3)2As + -ic entry 1; Kakodyl from Greek kakṓdēs "foul-smelling" (from kakós "bad, ill, foul" + -ōdēs "having a given smell," adjective derivative from od-, the base of ózein "to smell, give off odor") + German -yl -yl — more at caco-, odor
Note: According to Jöns Jakob berzelius, he suggested the name Kakodyl to the chemist Robert bunsen, who was investigating it, because of "the extremely repellent smell of all of its compounds" ("… für welche ich Bunsen den Namen Kakodyl vorschlug, in Bezug auf den höchst wiedrigen Geruch aller seiner Verbindungen" - Jahresbericht über die Fortschritte der physischen Wissenschaften von Jacob Berzelius, 20. Jahrgang [1841], p. 527).
First Known Use
1840, in the meaning defined above
Medical Definition
cacodylic acid
noun
cac·o·dyl·ic acid ˌkak-ə-ˌdil-ik-
: a toxic crystalline compound of arsenic C2H7AsO2 used especially as an herbicide