definition of
dorsum

[1] #1 dorsum n. [back] the posterior part of a human (or animal) body from the neck to the end of the spine; "his back was nicely tanned". wn

[2] #2 dorsum n. the back of the body of a vertebrate or any analogous surface (as the upper or outer surface of an organ or appendage or part); "the dorsum of the foot". wn