expositor
/ɪkˈspɒzɪtə(r)/noun
- a person or thing that explains complicated ideas or theories阐述者, 解释者; 起解释作用的东西：
a lucid expositor of difficult ideas.
一位头脑清楚的对疑难观点进行阐述的人。
词源
Middle English: via Old French or late Latin, from Latin exposit- 'exposed, explained', from exponere （see EXPOUND）.