Parliamentarian

A parliamentarian is a type of expert.

He is a great analyst and a great parliamentarian.

a parliamentarian democracy; the parliamentarian movement

1946, Office of United States Chief Counsel For Prosecution of Axis Criminality, Nazi Conspiracy and Aggression, Washington, Volume 1, citing Wilhelm Frick, Our participation in the parliament does not indicate a support, but rather an undermining of the parliamentarian system.

[...] Deputies were sent with Commissions into all the Counties; and the Parliamentarian Rebels by force and their own authority, invade the Militia, which they could not obtain from the King by petitioning.

But while he continued there, he shew’d himself a Dunce, a Tale-bearer to the Parliamentarian Visitors that then acted in the University, and a factious person.

The Scotch and parliamentarian army had joined, and were beſieging York; when prince Rupert, joined by the marquis of Newcaſtle, determined to raiſe the ſiege.

There were large regions which were very decidedly royalist, others almost as distinctly parliamentarian [...]