ˌstȯikēˈämə.trē noun
( -es )
Etymology: Greek stoicheion + English -metry
1. : a branch of science that deals with the application of the laws of definite proportions and of the conservation of matter and also energy to chemical reactions and processes
2.
a. : the quantitative relationship of constituents in a chemical entity
aquo-cations of definite stoichiometry characterize crystalline salts — Therald Moeller
b. : the quantitative relationship between two or more substances especially in processes involving physical or chemical change
the stoichiometry and reversibility of ion exchange — Robert Kunin