Meaning of microstructure

mi•cro•struc•ture

Pronunciation: (mī'krō-struk"chur), [key]
— n. Metall.
  1. the structure of a metal or alloy as observed, after etching and polishing, under a high degree of magnification.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.