trunk vs dorsum

trunk and dorsum both are nouns.

Word	Noun	Adjective	Verb	Adverb
trunk	Yes	No	No	No
dorsum	Yes	No	No	No

trunk (noun)	dorsum (noun)
a long flexible snout as of an elephant	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)
luggage consisting of a large strong case used when traveling or for storage	the posterior part of a human (or animal) body from the neck to the end of the spine
compartment in an automobile that carries luggage or shopping or tools
the body excluding the head and neck and limbs
the main stem of a tree; usually covered with bark; the bole is usually the part that is commercially useful for lumber