The term Church Militant is actually used by the Roman Catholic Church, though, unfortunately, not with the same meaning as the TV Tropes definition. As far as Catholics are concerned the Church Militant, a collective noun, consists of all members of the Church still living in this world. It's the sister term to:
Church Triumphant, those who have ascended to heaven;
Church Penitent, those in purgatory;
Church Visible, Christian members of a non-Catholic institutional church;
Church Invisible, all Christians regardless of denominational lines and divisions.
