[1] : The Collaborative International Dictionary of English v.0.48

decillion \decil"lion\, n. l. decem ten + the ending of
   million.
   according to the english notation, a million involved to the
   tenth power, or a unit with sixty ciphers annexed; according
   to the french and american notation, a thousand involved to
   the eleventh power, or a unit with thirty-three ciphers
   annexed. see the note under numeration.
   1913 webster
see also:
numeration 

Decillion >> D Words
Decillion, definition of term: Decillion
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