pre-equilibrium (prior equilibrium)

A rapidly reversible step preceding the rate-limiting step in a stepwise reaction. For example:
P04810
See also: kinetic equivalence
Source:
PAC, 1994, 66, 1077 (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1152
See also:
PAC, 1996, 68, 149 (A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)) on page 177