hip joint vs coxa

hip joint and coxa both are nouns.

Word	Noun	Adjective	Verb	Adverb
hip joint	Yes	No	No	No
coxa	Yes	No	No	No

As nouns, hip joint and coxa are synonyms defined as:

hip joint and coxa: the ball-and-socket joint between the head of the femur and the acetabulum

Other synonyms of hip joint include articulatio coxae, hip.

hip joint (noun)	coxa (noun)
the ball-and-socket joint between the head of the femur and the acetabulum	the ball-and-socket joint between the head of the femur and the acetabulum