stereochemistry Syllabification: (ster·e·o·chem·is·try)Pronunciation: /ˌsterē-ōˈkeməstrē, ˌsti(ə)r-/Definition of stereochemistry noun the branch of chemistry concerned with the three-dimensional arrangement of atoms and molecules and the effect of this on chemical reactions. Derivatives stereochemicalPronunciation: /-ˈkemikəl/ adjective stereochemically adverb stereochemistry in other Oxford dictionaries Definition of stereochemistry in the British & World English dictionary