Exponent /ɪkˈspoʊ.nənt/ n. (想法或信仰的)拥护者,鼓吹者;(某活动的)能手; 指数(15000)
meaning: a person who supports an idea or belief or performs an activity
1) 前缀: ex-向外
2) 词根:pon-放置(postpone)
3) 后缀:-ent 名词后缀(parent)
e.g. Adam Smith was an exponent of free trade. 亚当‧斯密提倡自由贸易。