1 a runnerless, tobogganlike sled usually drawn by dogs.
1831  (1963)  . . . John Hay and Mr. Taylor making flat sleds etc.
1897  The dog-sleds were not the same as those we had used in traversing the hard driven snow of the plains, but were what are known as "flat sleds" or large toboggans, they being better suited to woodland travel.
1922  Everything an Indian requires . . . is made with this knife -- canoes, flatsleds, snowshoes . . . .
2 a similar, somewhat larger sled, drawn by one or two horses.
1880  On Christmas Eve Mr. Brunette's horse ran away with the flat sled scattering the contents over the whole length of Ross' new grade.
1929  Sometimes I was off to the plains with horses and flat sleds for buffalo meat, sometimes shooting prairie chickens . . . .
1958  The gold seekers set out with horse-drawn flat sleds eventually.