microstructure

/ˈmaɪkroʊˌstrʌktʃər/
noun
  1. The small-scale structure of a material or object, visible only under a microscope.
    • The microstructure of steel determines its strength and flexibility.
    • Changes in the microstructure of the alloy can make it more resistant to corrosion.
    • Scientists studied the microstructure of the ancient pottery to learn how it was made.