trapezium vs carpal bone

trapezium and carpal bone both are nouns.

Word	Noun	Adjective	Verb	Adverb
trapezium	Yes	No	No	No
carpal bone	Yes	No	No	No

As nouns, carpal bone is a hypernym of trapezium; that is, carpal bone is a word with a broader meaning than trapezium:

trapezium: the wrist bone on the thumb side of the hand that articulates with the 1st and 2nd metacarpals
carpal bone: any of the eight small bones of the wrist of primates

Other hypernyms of trapezium include carpal, wrist bone.

trapezium (noun)	carpal bone (noun)
the wrist bone on the thumb side of the hand that articulates with the 1st and 2nd metacarpals	any of the eight small bones of the wrist of primates
a quadrilateral with no parallel sides