# sextillion

> English word · Numeral · IPA /sɛksˈtɪljən/

## Definitions
1. A trillion billion: 1 followed by 21 zeros, 10²¹.
2. A million quintillion: 1 followed by 36 zeros, 10³⁶.

## Etymology
From Classical Latin sextus (“sixth”) + -illion; originally the sixth power of a million, 10³⁶. Compare slightly earlier quintillion, Middle French sixlion (1484) and French sextillion (1765). First attested in 1689 in John Locke’s An Essay Concerning Human Understanding (see the quotation).

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/sextillion