Dehydration synthesis is a chemical reaction that involves the loss of a water molecule from the reacting molecules. It's often used to connect smaller molecules together into larger, more complex ones.
A monomer is a small molecule that can bind chemically with other molecules to form a polymer. In our Lego analogy, each individual block would be considered a monomer.
Polymer: A polymer is made up of many monomers linked together. This would be your completed Lego tower.
Condensation Reaction: This is another name for dehydration synthesis because during the process, water condenses out.