Stump Orator, one who is ready to take up any question of the day, usually a political one, and harangue upon it from any platform offhand; the class, the whole merely a talking one, form the subject, in a pretty wide reference, of one of Carlyle's scathing “Latter-Day Pamphlets.”
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Stukeley, William * Sturm, Johann