Binding of a substance, or its metabolites from a phase I reaction, with endogenous molecules (conjugation), making more water-soluble derivatives that may be excreted in the urine or bile.
Source:
PAC, 2004, 76, 1033. 'Glossary of terms used in toxicokinetics (IUPAC Recommendations 2003)' on page 1064 (https://doi.org/10.1351/pac200476051033)