micromillimeter

/ˌmaɪkroʊˈmɪlɪˌmitər/
noun
  1. A unit of length equal to one millionth of a meter; a micrometer.
    • The machine can cut materials with precision down to a single micromillimeter.
    • The width of a human hair is about 70 micromillimeters.
    • Scientists measured the dust particle at just a few micromillimeters across.
Synonyms