initiator

 Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++i·ni·ti·a·tor /ɪˈnɪʃieɪtə $ -ər/ AWL noun [countable]  someone who thinks of and starts a new plan or process 发起人，创始人initiator of the initiator of the proposal 该项提议的发起人

i·ni·ti·a·tor nounChineseSyllable  

initiator
i‧ni‧ti‧a‧tor AC /ɪˈnɪʃieɪtə $ -ər/ noun [countable]
someone who thinks of and starts a new plan or process
    initiator of
    the initiator of the proposal

ini·ti·ator AW BrE /ɪˈnɪʃieɪtə(r)/ 🔊NAmE /ɪˈnɪʃieɪtər/ 🔊 noun (formal) the person who starts sth 发起人；创始人