Define the term polymerization.

Hint: The term polymerization is derived out of the word ‘polymer’, here the term ‘Polymer’ comes from the Greek, meaning ‘many parts’. And polymerization is basically a process in which simple units (monomers) molecules react together in such a way to make chains or three-dimensional networks like molecules.

Complete answer:
A polymer may be a long molecule consisting of the many identical or similar building blocks linked by covalent bonds – like how a train consists of a sequence of cars. Most large molecules, or macromolecules, are polymers. The repeating units that function as the building blocks of a polymer are small molecules called monomers.
Polymerization is the process of connecting these monomers together and creating large macromolecules of different size and shapes. Polymerization is analogous to constructing an outsized building out of an equivalent sort of Lego block. The blocks can be connected in different ways to build a larger structure, more intricately shaped than the original Lego block on its own. A polymer is a large single chain-like molecule in which the repeating units derived from small molecules called monomers are bound together. The process by which simple molecular units (monomers) are converted into a polymer is called polymerisation.

Additional Information:
The two major sorts of polymerization are addition polymerization and condensation polymerization.
1. Addition Polymerization:
Polymerization that happens through the coupling of monomers using their multiple bonds is named addition polymerization.
Some common commercial addition polymers are:
• Polyethylene - films, packaging, bottles
• Polypropylene - kitchenware, fibres, appliances
• PVC - pipe fittings, clear film for meat packaging
2. Condensation Polymerization and Hydrolysis:
The mechanism that cells use to form and break polymers are basically an equivalent altogether. Monomers are connected by a reaction in which two molecules are covalently bonded to each other through loss of a water molecule; this is called a condensation polymerization because the lost molecule is water. When a bond forms between two monomers, each monomer contributes part of the water molecule that is lost; one molecule provides a hydroxyl group, while the other provides a hydrogen. To achieve a polymer chain, the reaction mentioned is repeated and one by one the monomers are added to the chain.
Some common commercial condensation polymers are:
Polyurethane
 Polyethylene terephthalate (a polyester)
Nylon 6,6
Some common polymers in life are:
Disaccharides and polysaccharides like maltose, sucrose, and glycogen.
All proteins made from amino acids.
Nucleic acids, like DNA and RNA, made from nucleotides

Note: - The term ‘Polymer’ comes from the Greek, meaning ‘many parts’.
- The process by which simple molecular units (monomers) are converted into a polymer is called polymerisation.
- The two major sorts of polymerization are addition polymerization and condensation polymerization.