micron

/ˈmaɪkrɑn/
noun
  1. A unit of length equal to one millionth of a meter, used to measure very small things like cells or dust particles.
    • The filter can trap particles as small as one micron.
    • A human hair is about 70 microns thick.
    • Scientists measured the bacteria at two microns in length.
Synonyms
What does "micron" mean? | whatsthatwordmean | whatsthatwordmean