In a @[email protected], the average number of times the closed cycle of reactions (involving the @[email protected]) is repeated. It is equal to the rate of the overall reaction divided by the rate of the @[email protected] reaction.
PAC, 1996, 68, 149. (A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)) on page 157 [Terms] [Paper]