Synthesis is the process of combining different elements or ideas to create something new. It involves taking separate parts and putting them together to form a whole. For example, in chemistry, synthesis refers to the production of a compound [a substance formed by the chemical combination of two or more elements] by combining different substances.
Very Simple Definition:
Synthesis is when you mix different things to make something new. In chemistry, synthesis means combining different stuff to create a compound, [a mix of two or more elements].