area of cardiac dullness vs thorax

area of cardiac dullness and thorax both are nouns.

Word	Noun	Adjective	Verb	Adverb
area of cardiac dullness	Yes	No	No	No
thorax	Yes	No	No	No

area of cardiac dullness (noun)	thorax (noun)
a triangular area of the front of the chest (determined by percussion); corresponds to the part of the heart not covered by the lungs	part of an insect's body that bears the wings and legs
	the part of the human torso between the neck and the diaphragm or the corresponding part in other vertebrates
	the middle region of the body of an arthropod between the head and the abdomen