Which word describes a substance that helps propel or drive something forward?

The term "propellant" specifically refers to a substance that is used to drive or propel something forward, particularly in contexts like rockets, engines, or various mechanisms requiring movement. It generates thrust or force, enabling an object to move from one place to another. In the context of propulsion, such substances react to create a high-pressure gas that pushes an object forward, which is a fundamental principle in both aerospace and automotive industries.

The other terms listed do not convey a similar meaning. For instance, a "magnate" refers to a wealthy and influential person, while "inhibit" indicates a decrease or prevention of activity. The word "cordially" means in a warm and friendly manner, which does not relate to propulsion or driving forces at all. Thus, "propellant" is the only term that accurately describes a substance intended to move something forward.