catalyst
/ˈkætəlɪst/noun
1- a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change催化剂; 触媒剂。
1.1
- figurative a person or thing that precipitates an event〈喻〉促进事情发展的人（或物）：
the prime minister's speech acted as a catalyst for debate.
首相的演讲对辩论起到促进作用。
词源
early 20th cent.: from CATALYSIS, on the pattern of analyst.