in•ter•sti•tialPronunciation: (in"tur-stish'ul), [key]
pertaining to, situated in, or forming interstices.
situated between the cells of a structure or part: interstitial tissue.
an imperfection in a crystal caused by the presence of an extra atom in an otherwise complete lattice. Cf. vacancy
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.