sep·​ten·​de·​cil·​lion (ˌ)sep-ˌten-di-ˈsil-yən How to pronounce septendecillion (audio)
often attributive
US : a number equal to 1 followed by 54 zeros see Table of Numbers
also, British : a number equal to 1 followed by 102 zeros see Table of Numbers

Word History


Latin septendecim seventeen (from septem seven + decem ten) + English -illion (as in million) — more at ten

First Known Use

1898, in the meaning defined above

Time Traveler
The first known use of septendecillion was in 1898

Dictionary Entries Near septendecillion

Cite this Entry

“Septendecillion.” Dictionary, Merriam-Webster, Accessed 5 Feb. 2023.

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