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

micra, micracoustic, micrencephaly, micrify, micro, micro-, micro-astrup method, micro-cap, micro-credit, micro-image, micro-scooter

Also especially before a vowel, micr-.

Origin of micro-

< Greek: combining form representing mīkrós small

Can be confused

macro- 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

Medicine definitions for micro-

micro-

pref.

Small:microblast.

Abnormally small:microcephaly.

Requiring or involving microscopy:microsurgery.

One-millionth (10-6):microliter.

Science definitions for micro-

micro-

A prefix that means: small (as in microorganism) or one millionth (as in microsecond).