Measure words denote a unit or measurement and are used with mass nouns (uncountable nouns), and in some cases also with count nouns. For instance, in English, mud is a mass noun and thus one cannot say "three muds", but one can say "three drops of mud", "three pails of mud", etc. In these examples, drops and pails function as measure words. One can also say "three pails of shells"; in this case the measure word pails accompanies a count noun (shells).
The term measure word is also sometimes used to refer to numeral classifiers, which are used with count nouns in some languages. For instance, in English no extra word is needed when saying "three people", but in many East Asian languages, since the words for nouns themselves don't contain morphemes that indicate their own singular and plural forms, a numeral classifier is added, just as a measure word is added for uncountable nouns in English. In cases where singular and plural forms need to be distinguished, a number and a measure word is added to the noun phrase. For example, to say one dog and three dogs in Chinese, one would need to say yīzhīgǒu (simplified 一只狗, traditional 一隻狗) and sānzhīgǒu (simplified 三只狗, traditional 三隻狗) respectively, which could be transliterated as one animal dog and three animal dog respectively. While many linguists maintain a distinction between measure words and numeral classifiers, the terms are sometimes used interchangeably. For instance, materials for teaching Chinese as a second language generally refer to Chinese classifiers as "measure words". The corresponding Chinese term is liàngcí (simplified 量词, traditional 量詞), which can be directly translated as "quantity word".
- one quart of water
- three cups of coffee
- four kernels of corn, three ears of corn, two bushels of corn
In many languages, including the East Asian languages referred to above, the analogous constructions do not include any equivalent of the English of. In German, for example, ein Glas Bier means "a glass [of] beer". This is interesting since both languages are West Germanic languages, making them closely related to each other. However, the equivalent of the English of is common in Romance languages such as Spanish, French, and Portuguese. In Spanish "a glass of beer" is "un vaso de cerveza", in French it is "un verre de bière", and in Portuguese it is "um copo de cerveja".
- Tai, James H.-Y. (1994). "Chinese classifier systems and human categorization". In Willian S.-Y. Wang, M. Y. Chen, and Ovid J.L. Tzeng. In honor of William S.-Y. Wang: Interdisciplinary studies on language and language change. Taipei: Pyramid Press. p. 2. ISBN 978-957-9268-55-4.
- Cheng, Lisa L.-S.; Sybesma, Rint (1998). "yi-wan tang and yi-ge Tang: Classifiers and mass-classifiers". Tsing Hua Journal of Chinese Studies. 28 (3).