chemical element, 1894, Modern Latin, from Greek argon, neuter of argos "lazy, idle, not working the ground, living without labor," from a- "without" (see a- (3)) + ergon "work," from PIE root *werg- "to do." So called by its discoverers, Baron Rayleigh and Sir William Ramsay, for its inert qualities. They described it as "most astonishingly indifferent."