[dih-sil-yuh n]


a cardinal number represented in the U.S. by 1 followed by 33 zeros, and in Great Britain by 1 followed by 60 zeros.


amounting to one decillion in number.

Origin of decillion

1835–45; < Latin dec(em) ten + -illion, as in million
Related formsde·cil·lionth, adjective, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for decillion

Historical Examples of decillion

  • The number of grains of sand in this sphere of the fixed stars would be a decillion decillion 6.

British Dictionary definitions for decillion



(in Britain, France, and Germany) the number represented as one followed by 60 zeros (10 60)
(in the US and Canada) the number represented as one followed by 33 zeros (10 33)
Derived Formsdecillionth, adjective

Word Origin for decillion

C19: from Latin decem ten + -illion as in million
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012