micron

or mi·kron

[mahy-kron]

noun, plural mi·crons, mi·cra

[mahy-kruh] /ˈmaɪ krə/.

Also called micrometer. the millionth part of a meter. Symbol: μ, mu
Physical Chemistry. a colloidal particle whose diameter is between 0.2 and 10 microns.
Physics. a very small unit of pressure, equal to that exerted by a column of mercury 1μ high.

Origin of micron

1880–85; < Greek mīkrón a little, noun use of neuter singular of mīkrós small; see -on¹

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for micron

Contemporary Examples of micron

Most of the particles generated by burning wood are smaller than one micron—a size believed to be most damaging to our lungs.
The Fireplace Delusion: A Metaphor for Religious Belief
Sam Harris
February 3, 2012

Historical Examples of micron

The man who studies bacteria measures by the micron, 25,000 of which go to the inch.
Rustic Sounds
Francis Darwin
But with the destruction of the planet an almost certainty, the collective nervous system was just one micron away from explosion.
Alien Offer
Al Sevcik
This unit is the one-thousandth part of a millimeter and is called the micro-millimeter or micron.
The Fundamentals of Bacteriology
Charles Bradfield Morrey
Their size is measured by the unit used in the microscope, called the micron, which is about 1⁄25000 of one inch.
Foods and Household Management
Helen Kinne

British Dictionary definitions for micron

micron

noun plural -crons or -cra (-krə)

a unit of length equal to 10 –6 metre. It is being replaced by the micrometre, the equivalent SI unit

Word Origin for micron

C19: New Latin, 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 micron

"one millionth of a meter," 1892, coined 1880 in French from Greek mikron, neuter of mikros "small" (see mica).

micron in Medicine