Milli
/ˈmɪl.i/noun
A metric prefix meaning one-thousandth (10⁻³).
Did you know?Milli comes from Latin *mille* meaning “thousand,” the same root behind *millennium* and *millepede*—a reminder that even the smallest scale in science is built on an ancient word for abundance.
Etymological Timeline
Proto-Indo-European
PIE
*sm̥h₁lós / *m̥h₁l-
“A root associated with the number one thousand”
Latin
Latin
mille
“One thousand”
French
Old French
mille
“One thousand”
19th Century
French
milli-
“A metric prefix meaning one-thousandth”
Modern English
English
milli-
“A standard SI prefix meaning one-thousandth (10⁻³)”
Explore more surprising origins