un·​de·​cil·​lion ˌən-di-ˈsil-yən How to pronounce undecillion (audio)
often attributive
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

Word History


Latin undecim eleven (from unus one + decem ten) + English -illion (as in million) — more at one, ten

First Known Use

1844, in the meaning defined above

Time Traveler
The first known use of undecillion was in 1844

Dictionary Entries Near undecillion

Cite this Entry

“Undecillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undecillion. Accessed 21 Jul. 2024.

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