mass noun

n. noun which has no plural form, noun which is not used with the article "a" or "an" (such as cattle, happiness, luggage)

In linguistics, a mass noun (also uncountable noun or non-count noun) is a common noun that presents entities as an unbounded mass. Given that different languages have different grammatical resources, the actual test for which nouns are mass nouns may vary from language to language. In English, mass nouns are characterized by the fact that they cannot be directly modified by a numeral without specifying a unit of measurement, and that they cannot combine with an indefinite article (a(n)). Mass nouns combine with expressions like too much ("too much water"), while count nouns don't (*"too much chair(s)").
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Noun
1. a noun that does not form plurals
(hypernym) noun

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