a noun denoting something which cannot be counted (e.g. a substance or quality), in English usually a noun which lacks a plural in ordinary usage and is not used with the indefinite article, e.g. luggage, china, happiness

【语法】 不可数名词。与COUNT NOUN相对。

a noun denoting something which normally cannot be counted but which may be countable when it refers to different units or types, e.g. coffee, bread (drank some coffee, ordered two coffees; ate some bread, stocks several different breads)

物质名词，整体名词。