knee joint vs genu

knee joint and genu both are nouns.

Word	Noun	Adjective	Verb	Adverb
knee joint	Yes	No	No	No
genu	Yes	No	No	No

As nouns, knee joint and genu are synonyms defined as:

knee joint and genu: hinge joint in the human leg connecting the tibia and fibula with the femur and protected in front by the patella

Other synonyms of knee joint include articulatio genus, human knee, knee.

knee joint (noun)	genu (noun)
hinge joint in the human leg connecting the tibia and fibula with the femur and protected in front by the patella	hinge joint in the human leg connecting the tibia and fibula with the femur and protected in front by the patella