enarthrosis vs synovial joint

enarthrosis and synovial joint both are nouns.

Word	Noun	Adjective	Verb	Adverb
enarthrosis	Yes	No	No	No
synovial joint	Yes	No	No	No

As nouns, synovial joint is a hypernym of enarthrosis; that is, synovial joint is a word with a broader meaning than enarthrosis:

enarthrosis: a freely moving joint in which a sphere on the head of one bone fits into a rounded cavity in the other bone
synovial joint: a joint so articulated as to move freely

Other hypernyms of enarthrosis include articulatio synovialis, diarthrosis.

enarthrosis (noun)	synovial joint (noun)
a freely moving joint in which a sphere on the head of one bone fits into a rounded cavity in the other bone	a joint so articulated as to move freely