An uncountable noun, also known as a mass noun, refers to something that cannot be counted as individual units or separate elements. These nouns are usually substances, concepts, or qualities that cannot be divided into separate parts. Uncountable nouns are usually singular and do not have a plural form.
Uncountable nouns are used with singular verbs and do not have an "s" added to form a plural. They are often preceded by words like "some," "any," "a lot of," or "much."