Fires up is a term that can be used to describe a variety of activities. STOKES (6 letters) is an action that involves stirring or agitating something, often with a stick or rod. Arouses (7 letters) is an action that causes someone to become alert and interested. REVS (4 letters) is an action that involves increasing the speed of an engine or motor. IGNITES (7 letters) is an action that involves setting something on fire. Excites (7 letters) is an action that causes someone to feel enthusiastic and eager. Psychs (6 letters) is an action that involves mentally preparing oneself for a task. Peps (4 letters) is an action that involves encouraging someone to feel more energetic and enthusiastic. Incites (7 letters) is an action that encourages someone to do something, often something that is wrong or dangerous. All of these actions can be used to describe the term 'fires up'.