polymerization

n. combination of two or more separate molecules to form a more complex molecule (also polymerisation)

For polymerization in DNA, see DNA polymerase. In polymer chemistry, polymerization is a process of bonding monomers, or "single units" together through a variety of reaction mechanisms to form longer chains named polymers. Polymers exist as a variety of 3-dimensional shapes, each with specific individual properties relevant to the monomers or reaction mechanisms they are formed from.
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Polymerization /po·lym·er·iza·tion/ the combining of several simpler molecules to form a polymer. po·lym·er·i·za·tion n. 1. [more]Polymerization - Community and Resources

Noun
1. a chemical process that combines several monomers to form a polymer or polymeric compound
(synonym) polymerisation
(hypernym) chemical process, chemical change, chemical action
(derivation) polymerize, polymerise

(n.)
The act or process of changing to a polymeric form; the condition resulting from such change.