a combining form meaning “thousand” (millipede): in the metric system, used in the names of units equal to one thousandth of the given base unit (millimeter).

Nearby words

  1. millet,
  2. millet, francis davis,
  3. millet, jean françois,
  4. millett,
  5. millhouse,
  6. milliammeter,
  7. milliampere,
  8. milliard,
  9. milliary,
  10. millibar

Origin of milli-

< French < Latin, combining form of mille thousand Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for milli-



denoting 10 –3millimetre Symbol: m

Word Origin for milli-

from French, from Latin mille thousand, this meaning being maintained in words borrowed from Latin (millipede)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for milli-


word-forming element meaning "thousandth part of a metric unit," from comb. form of Latin mille "thousand" (see million).

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for milli-



One thousandth (10-3):millisecond.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for milli-


A prefix that means “one thousandth,” as in millimeter, one thousandth of a meter.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.