blood count vs counting

blood count and counting both are nouns.

Word	Noun	Adjective	Verb	Adverb
blood count	Yes	No	No	No
counting	Yes	No	No	No

As nouns, counting is a hypernym of blood count; that is, counting is a word with a broader meaning than blood count:

blood count: the act of estimating the number of red and white corpuscles in a blood sample
counting: the act of counting; reciting numbers in ascending order

Other hypernyms of blood count include count, enumeration, numeration, reckoning, tally.

blood count (noun)	counting (noun)
the act of estimating the number of red and white corpuscles in a blood sample	the act of counting; reciting numbers in ascending order
the number of red and white corpuscles in a blood sample