baseburner, n. — Green’s Dictionary of Slang

baseburner n.

[SE base-burner, ‘a sheet-iron stove for burning anthracite coal, which is only fed at the top, while the fire is confined to the base, or lower part of the stove’ (Bartlett, Dict. Americanisms, 1877)]

(US) the buttocks.

1883

G.W. Peck Peck’s Bad Boy and His Pa (1887) 149: Come out here and bring in that kindling wood, or I will start a fire on your base-burner with this strap.