mortise joint vs gliding joint

mortise joint and gliding joint both are nouns.

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

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

mortise joint: a gliding joint between the distal ends of the tibia and fibula and the proximal end of the talus
gliding joint: a freely moving joint in which the articulations allow only gliding motions

Other hypernyms of mortise joint include articulatio plana.

mortise joint (noun)	gliding joint (noun)
a joint made by inserting tenon on one piece into mortise holes in the other	a freely moving joint in which the articulations allow only gliding motions
a gliding joint between the distal ends of the tibia and fibula and the proximal end of the talus