'micron' definitions:

Definition of 'micron'

(from WordNet)
noun
A metric unit of length equal to one millionth of a meter [syn: micron, micrometer]

Definition of 'micron'

From: GCIDE
  • Micromillimeter \Mi`cro*mil"li*me`ter\, n. [Micro- + millimeter.] The millionth part of a meter.
  • Note: The millionth part of a meter is now termed a micron, and the word micromillimeter does not conform to the IS use of the prefix micro-. [1913 Webster +PJC]

Definition of 'micron'

From: GCIDE
  • micron \mic"ron\, n. [NL., fr. Gr. mikro`s small.] (Physics) A measure of length; the thousandth part of one millimeter; the millionth part of a meter. [1913 Webster]