Cacodyl n. : Alkarsin; a colorless, poisonous, arsenical liquid, As2(CH3)4, spontaneously inflammable and possessing an intensely disagreeable odor. It is the type of a series of compounds analogous to the nitrogen compounds called hydrazines.

Example:
What is the molecular formula of Cacodyl?

Taxonomy
CH3, Cacodyl oxide, free encyclopedia, smell, 2As, liquid, As2, dimethyl, arsine, radical theory, History, reaction conditions, arsenic compounds, compounds, evil effects, search, Identifiers, the French.

Defination from the web:
Cacodyl, dicacodyl, tetramethyldiarsine, alkarsine or minor part of the "Cadet's fuming liquid" (after the French chemist Louis Claude Cadet de ... Jöns Jakob Berzelius coined the name kakodyl (later changed to cacodyl) for the dimethylarsinyl radical, (CH3)2As, from the Greek kakodes (evil ...