gliding joint vs synovial joint

gliding joint and synovial joint both are nouns.

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

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

gliding joint: a freely moving joint in which the articulations allow only gliding motions
synovial joint: a joint so articulated as to move freely

Other hypernyms of gliding joint include articulatio synovialis, diarthrosis.

gliding joint (noun)	synovial joint (noun)
a freely moving joint in which the articulations allow only gliding motions	a joint so articulated as to move freely