Count noun

A count noun is a noun which can be modified by a numeral and occur in both singular and plural form, as well as co-occurring with quantificational determiners like every, each, several, most, etc. A mass noun has none of these properties. It can't be modified by a numeral, occur in singular/plural or co-occur with the relevant kind of determiner. Below we see examples of all these properties for the count noun cow and the mass noun cattle. As always in linguistic jargon, a star "*" in front of a sentence is intended to mean that that sentence is odd or ill-formed.

• Modification by numeral:

We saw seven cows in the garden.

*We saw seven cattle(s) in the garden.

• Occurrence in plural/singular.

There is a cow in the garden.

There are cows in the garden.

There is cattle in the garden.

*There are cattles in the garden.

• Co-occurrence with count determiners

Every cow is an animal.

There are several cows in the garden.

*Every cattle is an animal.

*There are several cattles in the garden.

Some determiners can be used with both mass and count nouns, including "some", "a lot (of)", "no".

A common misunderstanding concerning the mass/count distinction is that it is based on the type of thing the different nouns refer to. Mass nouns are thought to refer to things (or substances) that can't be counted, while count nouns are supposed to refer to ones that can. That this can't be right is seen with our examples above, using cow (count) and cattle (mass). If we have seven cows in the garden, they can be described both as "cows" and as "cattle". The mass/count distinction must therefore pertain to the expressions themselves ("cow" vs. "cattle") and not to the things they refer to. One may say that the noun "cattle" present the cows as a mass, while the noun "cow" presents them as individuated specimens. Some substances have physical properties which makes it difficult to refer to them with a count noun. For example, it is difficult to think about air as individuated chunks (unless we are discussing air at a molecular level). Consequently, we tend to refer to air with the mass noun "air". If we specify the unit of measurement, we can refer to even such substances as count, as in "two litres of wine". But the mass/count distinction remains a grammatical classification of expressions and not the sort of thing they refer to.

Following the work of logicians like Godehard Link and Manfred Krifka, we know that the mass/count distinction can be given a precise mathematical definition in terms of notions like cumulativity and quantization.

Some languages treat all nouns as basically mass, and need to make use of a noun classifier to add numerals and other quantifiers. To take an example from Mandarin Chinese, which marks count(ed) nouns with a noun classifier:

Na4 ren2 chi1 wan2 le

can equally well mean "That person has eaten" or "Those people have eaten" - you're not counting them, so you don't need a classifier, and Mandarin doesn't distinguish singular vs. plural

Na4 wei4 ren2 chi1 wan2 le, means "That (one) person has eaten"

Na4 san1 wei4 ren2 chi1 wan2 le, means "Those three people have eaten"

A classifier, therefore, implies that the object(s) referred to are countable in the sense that the speaker intends them to be enumerated, rather than considered as a unit (regardless of quantity).

On the other hand, words such as "milk" or "rice" are not count nouns, but they can be counted with an appropriate unit of measure (e.g. "glasses of milk" or "spoonfuls of rice"). This leads to another example from Mandarin to illustrate some further points about count nouns:

• Ta1 you3 qi1 ben3 shu1 zai4 zhuo1-zi shang4. "She has seven books on the table".
• Ta1 xie3 wan2 qi1 ben3 shu1. "She has written seven books".

In both cases, the word "book" is a count noun, and in Mandarin take the classifier "ben3"

This use of a classifier is similar to, but not identical with, the use of units of measure to count groups of objects in English. For example, in "three shelves of books", "shelves" is used as a unit of measurement, and books is indeed a mass noun, since the speaker is not counting individual books - she is counting shelves of books. By contrast, in the sentence "At 10 books per shelf, you have 30 books," both instances of "books" are an example of a count noun, and require a "measure word" in Chinese (or, as linguists sometimes call it, a "noun classifier", of which measure words are one type).

Different languages may treat "measured nouns" differently from "count nouns"; some, like Mandarin, will require a classifier before the unit of measure, while others may not require them at all. San1 bei bei1-zi mian4 "Three [classifier] cups (of) noodles" versus San1 kuai4 mian4 "Three [classifier] noodles". (Notice that the classifier changes as what is counted (cups vs. noodles) changes!)

Additional examples:
Count	Mass
Many waters	Much water
A few pies	Some pie
Some bananas	Some banana