Definify.com
Webster 1913 Edition
Quadrillion
Quad-ril′lion
,Noun.
[F., fr. L.
quater
four times, akin to quattuor
four, E. four
; – formed like million
. See Four
, Million
.] 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
.