parliamentarian

noun

1. a person who is expert in the formal rules and procedures of deliberative assemblies and other formal organizations.
2. (sometimes initial capital letter) British. a member of Parliament.
3. (initial capital letter) a partisan of the British Parliament in opposition to Charles I.

noun

1. an expert in parliamentary procedures, etc
2. (sometimes capital) British a Member of Parliament

adjective

3. of or relating to a parliament or parliaments

noun

1. a supporter of Parliament during the English Civil War

adjective

2. of or relating to Parliament or its supporters during the English Civil War

n.1640s as a designation of one of the sides in the English Civil War; meaning “one versed in parliamentary procedure” dates from 1834. See parliamentary + -ian.