catalyst
n. countablen. something that makes a change or an event happen much faster. In science, it is a substance that speeds up a chemical reaction without being used up itself.
n. a substance that increases the rate of a chemical reaction without undergoing any permanent chemical change. In a figurative sense, it refers to a person or event that precipitates a significant change or action.
The new manager was a catalyst for positive change.
Adding a small amount of platinum to the mixture acts as a catalyst, allowing the reaction to occur at room temperature.
Historians often argue whether the assassination was the primary cause of the war or merely the catalyst that ignited long-standing regional tensions.
From catalysis + -ist.
Often followed by the preposition 'for' when used in a figurative or social context.