ignite

An ignition happens when something starts burning or producing flames.

When we say "ignite", we often talk about starting fires. You might see it used on warning labels for matches or lighters that say not to ignite anything flammable. It can also mean sparking an idea, emotion, or action. For example, a passionate speech might ignite the crowd's enthusiasm. In chemistry and engineering, ignite has a more technical meaning: it refers to the point at which fuel reacts with oxygen and starts burning.