Meaning of stereoisomerism

ster•e•o•i•som•er•ism

Pronunciation: (ster"ē-ō-ī-som'u-riz"um, stēr"-), [key]
— n. Chem.
  1. the isomerism ascribed to different relative positions of the atoms or groups of atoms in the molecules of organic compounds.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.