prothrombin vs clotting factor

prothrombin and clotting factor both are nouns.

Word	Noun	Adjective	Verb	Adverb
prothrombin	Yes	No	No	No
clotting factor	Yes	No	No	No

As nouns, clotting factor is a hypernym of prothrombin; that is, clotting factor is a word with a broader meaning than prothrombin:

prothrombin: a protein in blood plasma that is the inactive precursor of thrombin
clotting factor: any of the factors in the blood whose actions are essential for blood coagulation

Other hypernyms of prothrombin include coagulation factor.

prothrombin (noun)	clotting factor (noun)
a protein in blood plasma that is the inactive precursor of thrombin	any of the factors in the blood whose actions are essential for blood coagulation