prefix ·Rare ·Advanced level

Definitions

Prefix

1. 1
   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). morpheme

Antonyms

All antonyms

atto

Etymology

From Ancient Greek ἕξ (héx, “six”), for the sixth order of 10³, analogous to tera-.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.