genu vs knee joint

genu and knee joint both are nouns.

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

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

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

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

genu (noun)	knee joint (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