quindecillion

noun

quin·​de·​cil·​lion ˌkwin-di-ˈsil-yən How to pronounce quindecillion (audio)
often attributive
US : a number equal to 1 followed by 48 zeros see Table of Numbers
also, British : a number equal to 1 followed by 90 zeros see Table of Numbers

Word History

Etymology

Latin quindecim fifteen (from quinque five + decem ten) + English -illion (as in million) — more at ten

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of quindecillion was in 1848

Rhymes for quindecillion

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Browse Nearby Words

quindecemvirate
quindecillion
quindecim
See all Nearby Words

Cite this Entry

“Quindecillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quindecillion. Accessed 6 Jul. 2026.

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