cacodyl

 
Pronunciation: /ˈkakə(ʊ)dʌɪl, -dɪl/

noun

[mass noun] Chemistry
  • a malodorous, toxic, spontaneously flammable liquid compound containing arsenic.
    • Chemical formula: ((CH3)2As)2
  • [as modifier] of or denoting the radical As(CH3)2, derived from cacodyl.

Origin:

mid 19th century: from Greek kakōdēs 'stinking' (from kakos 'bad') + -yl