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duodecillion

noun

duo·​de·​cil·​lion ˌdü-ō-di-ˈsil-yən How to pronounce duodecillion (audio)
ˌdyü-
often attributive
US : a number equal to 1 followed by 39 zeros see Table of Numbers
also, British : a number equal to 1 followed by 72 zeros see Table of Numbers

Word History

Etymology

Latin duodecim twelve + English -illion (as in million)

First Known Use

1844, in the meaning defined above

Time Traveler
The first known use of duodecillion was in 1844

Browse Nearby Words

Cite this Entry

“Duodecillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/duodecillion. Accessed 26 Nov. 2025.

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