Noun
Grenvillite (plural Grenvillites)
(historical) A member of a political faction supporting the Grenville family, especially George Grenville.
After a decade of factional chaos, with distinct " Grenvillite ", " Bedfordite ", " Rockinghamite ", and " Chathamite " factions successively in power, and all referring to themselves as "Whigs", a new system emerged with two separate opposition groups. Source: Internet