oc·​to·​de·​cil·​lion ˌäk-tō-di-ˈsil-yən How to pronounce octodecillion (audio)
US : a number equal to 1 followed by 57 zeros see Table of Numbers
also, British : a number equal to 1 followed by 108 zeros see Table of Numbers

Word History


Latin octodecim eighteen + English -illion (as in million)

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of octodecillion was in 1848

Dictionary Entries Near octodecillion

Cite this Entry

“Octodecillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/octodecillion. Accessed 29 Nov. 2023.

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