Term: macromonomer molecule https://doi.org/10.1351/goldbook.M03670 Definition: A macromolecule that has one end-group which enables it to act as a monomer molecule, contributing only a single monomeric unit to a chain of the final macromolecule. Related Terms: 1) macromolecule (http://doi.org/10.1351/goldbook.M03667). 2) monomer molecule (http://doi.org/10.1351/goldbook.M04019). 3) monomeric unit (http://doi.org/10.1351/goldbook.M04018). 4) end-group (http://doi.org/10.1351/goldbook.E02092). Source: PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2290 (https://doi.org/10.1351/pac199668122287) Citation: 'macromonomer molecule' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03670 License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.