A term polymer is used when a long chain of monomer forms a macromolecule called polymer. This process is called polymerization. Monomers are the smaller individual units of long polymeric chain.
A long chain of amino acids form a protein macromolecule. Here protein is a polymer formed from monomers called amino acid. But, this is not the same with the lipids. A lipid is formed by the joining of fatty acid and a glycerol molecule. Such fatty acids may be saturated or unsaturated depending on the presence or absence of double bond in their structure.