catalyst
UK: ˈkætəlɪst | US: ˈkætəlɪst
n. a substance that increases the rate of a chemical reaction without itself undergoing any permanent change
n. a person or thing that precipitates an event or change
The word "catalyst" originates from the Greek katalysis, meaning "dissolution" or "loosening down." The prefix cata- (thoroughly) combines with lyst (from lyein, "to loosen"), reflecting the idea of breaking down or accelerating a process. In chemistry, it was first used in the 19th century to describe substances that "loosen" chemical bonds to speed reactions. The figurative sense of a "person/thing triggering change" emerged later.
Enzymes act as biological catalysts in metabolic reactions.
Her speech became a catalyst for social reform.
Platinum is a common catalyst in hydrogen fuel cells.
The protest served as a catalyst for policy changes.
Financial crises often act as catalysts for economic innovation.