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Webster 1913 Edition
Septillion
Sep-til′lion
,Noun.
[F.
septilion
, formed fr. L. septem
seven, in imitation of million
.] According to the French method of numeration (which is followed also in the United States), the number expressed by a unit with twenty-four ciphers annexed. According to the English method, the number expressed by a unit with forty-two ciphers annexed. See
Numeration
.