exa- (English)
Where does "exa-" come from?
The prefix 'exa-' derives from the Ancient Greek word 'héx,' meaning 'six.' It was coined as a technical term for the metric system to represent the sixth power of a thousand (10¹⁸). This linguistic building block follows the same pattern as 'tera-,' using Greek numeral origins to denote large-scale scientific multipliers.
Full etymology tree
- exa- (English), 'In the International System of Units and other metric systems of units, multiplying the unit to which it is attached by 10¹⁸ (a short scale quintillion or long scale trillion).'
- derived ἕξ (héx) (Ancient Greek), 'six'
- inherited *hwéks (Proto-Hellenic), 'six'
- inherited *swéḱs (Proto-Indo-European), 'six'
- inherited *hwéks (Proto-Hellenic), 'six'
- derived ἕξ (héx) (Ancient Greek), 'six'
Updated July 2026
Etymology data from Wiktionary, CC BY-SA 4.0 · About Miraris