stimulant
noun [ C ] uk/ˈstɪm.jə.lənt/ us/ˈstɪm.jə.lənt/
刺激物；激励物
something that makes or causes something else to grow or develop
Tourism has acted as a stimulant to the country's economy. 旅游业成为该国经济发展的一个促进因素。
兴奋剂
a substance, such as a drug, that makes the mind or body more active
Caffeine, which is found in coffee and tea, is a mild stimulant. 咖啡和茶中含有的咖啡因是轻度兴奋剂。