human elbow vs cubitus

human elbow and cubitus both are nouns.

Word	Noun	Adjective	Verb	Adverb
human elbow	Yes	No	No	No
cubitus	Yes	No	No	No

As nouns, human elbow and cubitus are synonyms defined as:

human elbow and cubitus: hinge joint between the forearm and upper arm and the corresponding joint in the forelimb of a quadruped

Other synonyms of human elbow include articulatio cubiti, cubital joint, elbow, elbow joint.

human elbow (noun)	cubitus (noun)
hinge joint between the forearm and upper arm and the corresponding joint in the forelimb of a quadruped	hinge joint between the forearm and upper arm and the corresponding joint in the forelimb of a quadruped
	the arm from the elbow to the fingertips