ultraroyalist

adjective

ul·​tra·​roy·​al·​ist ˌəl-trə-ˈrȯi-ə-list 

: characterized by extreme devotion to and support of a monarch or monarchy

ultraroyalist factions

ultraroyalist noun

plural ultraroyalists

Last September he unseated the divisive Tony Abbott, a social conservative and ultraroyalist, as the Liberals' leader and prime minister.

—The Economist

Word History

First Known Use

1821, in the meaning defined above