micro-


a combining form with the meanings “small” (microcosm; microgamete), “very small in comparison with others of its kind” (microcassette; microlith), “too small to be seen by the unaided eye” (microfossil; microorganism), “dealing with extremely minute organisms, organic structures, or quantities of a substance” (microdissection; microscope), “localized, restricted in scope or area” (microburst; microhabitat), “(of a discipline) focusing on a restricted area” (microeconomics), “containing or dealing with texts that require enlargement to be read” (microfilm; microreader), “one millionth” (microgram).

Nearby words

  1. micra,
  2. micracoustic,
  3. micrencephaly,
  4. micrify,
  5. micro,
  6. micro-astrup method,
  7. micro-cap,
  8. micro-credit,
  9. micro-image,
  10. micro-organism

Also especially before a vowel, micr-.

Origin of micro-

< Greek: combining form representing mīkrós small

Can be confusedmacro- micro-

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019


British Dictionary definitions for micro-

micro-

micr-

combining form

small or minutemicrospore
involving the use of a microscopemicrography
indicating a method or instrument for dealing with small quantitiesmicrometer
(in pathology) indicating abnormal smallness or underdevelopmentmicrocephaly; microcyte Compare macro- (def. 2)
denoting 10 –6microsecond Symbol: μ

Word Origin for micro-

from Greek mikros small

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 micro-

micro-

word-forming element meaning "small, microscopic; magnifying; one millionth," from Latinized comb. form of Greek mikros "small, little, petty, trivial, slight" (see mica).

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for micro-

micro-

pref.

Small:microblast.
Abnormally small:microcephaly.
Requiring or involving microscopy:microsurgery.
One-millionth (10-6):microliter.

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

Science definitions for micro-

micro-

A prefix that means: “small” (as in microorganism) or “one millionth” (as in microsecond).
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.