quadrillion — ONAD

quadrillion /kwäˈdrilyən, kwɑˈdrɪljən

▸ cardinal number

(plural quadrillions or (with numeral or quantifying word) same)

a thousand raised to the power of five (1015).

▪ dated, mainly British a septillion, that is, a thousand raised to the power of eight (1024).

– DERIVATIVES
quadrillionth /-ˈdrilyənT͟H/ ordinal number

– ORIGIN late 17th century : from French, from million, by substitution of the prefix quadri- ‘four’ for the initial letters.