A spontaneous process is a chemical reaction that occurs without an external force applied to it. It is a natural process that occurs on its own, without the need for any intervention. There are several synonyms for the term "spontaneous process" that are commonly used in scientific literature. Some of these include natural process, autochthonous process, self-generating process, and intrinsic process. These terms all refer to processes that occur on their own, without any outside influence or control. Whether referred to as spontaneous, natural, or intrinsic, these processes are fundamental to many aspects of chemistry, biology, and physics, and are essential to our understanding of the natural world.