from The American Heritage® Dictionary of the English Language, 4th Edition
- One thousandth (10-3): millisecond.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- In the International System of Units and other metric systems of units, one-thousandth of the unit to which it is prefixed; that is, multiplying the unit to which it is attached by 10-3. Symbol: m.
- thousand; one-thousandth.
from the GNU version of the Collaborative International Dictionary of English
- A prefix denoting a thousandth part of.
Latin mīlli-, from mīlle, thousand; see gheslo- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Latin mille ("thousand"), via French. (Wiktionary)