https://doi.org/10.1351/goldbook.C01153
The formation of a covalent bond by the combination or recombination of two radicals (the reverse of unimolecular homolysis). For example:
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1097 [Terms] [Paper]