A count noun is a noun whose possible referents are thought of as separate entities.
It thus has the ability:
to occur with distinctive determiners (such as a/an, many), and
It does not have the ability, however, to occur with a determiner such as much.
Some nouns permit treatment as either count or mass nouns .
For example, in English, salad may be treated as either a count or mass noun, as evidenced by the acceptability of the following expressions:
The word farmer is an example of a count noun, as evidenced by the acceptability of the following expressions:
However, the expression much farmer is not acceptable.
Quirk, Randolph, S. Greenbaum, G. Leech, and J. Svartvik. 1985.A comprehensive grammar of the English language. London: Longman.
Mish, Frederick (editor). 1991.Webster's ninth new collegiate dictionary. Springfield, MA: Merriam-Webster. 1,564 pages. 0877795088; indexed 0877795096; deluxe 087779510X.
Crystal, David. 1985.A dictionary of linguistics and phonetics. 2nd edition. New York: Basil Blackwell.