Micrometre

A micrometre (the American spelling is micrometer; symbol is µm) is a unit of length in the SI measurement system. It can also be called a micron. It is one millionth of a metre. A micrometre is often used as a measurement for small things like bacteria. Like the Angstrom it is used for radiation in or near the visible spectrum.

 Related pages 
Nanometre

Category:Units of length
Category:SI units