parliamentarian
noun [ C ] uk/ˌpɑː.lɪ.menˈteə.ri.ən/ us/ˌpɑːr.lə.menˈter.i.ən/
议会议员，（尤指）资深议员
a member of a parliament, especially one who is respected for his or her experience and skill
US议会法规专家
someone who is an expert on the rules and methods used by a group that makes laws or decisions