addition

https://doi.org/10.1351/goldbook.A00132
  1. Refers to addition reaction or addition transformation.
  2. Loosely, the formation of an adduct. (For an example, see Lewis acid.)
  3. Loosely, any association or attachment.
Source:
PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1081 (https://doi.org/10.1351/pac199466051077)