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un·de·cil·lion | \ ˌən-di-ˈsil-yən 
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\Definition of undecillion
US : a number equal to 1 followed by 36 zeros — see Table of Numbers also, British : a number equal to 1 followed by 66 zeros — see Table of Numbers
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Time Traveler for undecillion
The first known use of undecillion was in 1844
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