Quadrillion
Pronunciation : Quad*ril"lion
Part of Speech : n.
Etymology : [F., fr. L. quater four times, akin to quattuor four, E. four; -- formed like million. See Four, Million.]
Definition : Defn: According to the French notation, which is followed also upon the Continent and in the United States, a unit with fifteen ciphers annexed; according to the English notation, the number produced by involving a million to the fourth power, or the number represented by a unit with twenty-four ciphers annexed. See the Note under Numeration.
Source : Webster's Unabridged Dictionary, 1913