(transitive, especially of horses or riders) To run faster than; to outdistance.
1869, Leo Tolstoy, War and Peace, trans. Louise and Aylmer Maude, ch. 14,
He had lately procured himself a large, fine, mettlesome, Donets horse, dun-colored, with light mane and tail, and when he rode it no one could outgallop him.