Word Study
septillion
CIDE DICTIONARY
septillion, n. [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. [1913 Webster]
OXFORD DICTIONARY
septillion, n. (pl. same) a thousand raised to the eighth (or formerly, esp. Brit., the fourteenth) power (10(24) and 10(42) respectively).
Etymology
F f. sept seven, after billion etc.
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