Propagation is the step in a polymerization mechanism, where new monomer molecules are added to the growing polymer chain in the free radical process.
Termination is the final step in a free radical mechanism that results in the stopping of the free radical reaction.
Generalic, Eni. "Radikal." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
Glossary
Periodic Table