number (grammar)

Glossary of Grammatical and Rhetorical Terms

Each of these twins (plural) is a twin (singular). (James Woodson/Getty Images)


In English grammar, number refers to the grammatical contrast between singular (the concept of one) and plural (more than one) forms of nouns, pronouns, determiners, and verbs.

Although most English nouns form the plural by adding -s or -es to their singular forms, there are numerous exceptions. (See Plural Forms of English Nouns.)

See Examples and Observations below. Also see:

From the Latin, "number, division"

Examples and Observations

  • "The singular form of nouns is the unmarked and most common form, and plural nouns are formed from the singular by inflectional change, normally the addition of a suffix.

    "The overwhelming majority of nouns form their plural by adding the ending -(e)s. . . .

    "The normal spelling is -s, but if the word ends in s, z, x, sh, or ch, the spelling is -es: bus--buses, box--boxes, bush--bushes, match--matches.

    "If the singular ends in a consonant letter + -y, the spelling is -ies: copy--copies, fly--flies, lady--ladies, army--armies.

    "If the singular ends in a vowel letter + -y, however, the spelling is -s: boy--boys, day--days, key--keys, essay-essays.

    "If the singular ends in -o, the spelling of the plural is sometimes -os and sometimes -oes: pianos, radios, videos v. heroes, potatoes, volcanoes."
    (Douglas Biber, et al., The Longman Student Grammar of Spoken and Written English. Pearson, 2002)
  • The Plurals of Compound Nouns
    "For compound nouns written as one word, make the last part of the compound plural (briefcases, mailboxes). For compound nouns written as separate or hyphenated words, make the most important part plural: brothers-in law, lieutenant governors. . . .

    "Determiners are words that identify or quantify a noun, such as this study, all people, his suggestions. . . . Some determiners, such as a, an, this, that, one, and each, can only be used with singular nouns; others, such as these, those, all, both, many, several, and two, can only be used with plural nouns."
    (Andrea Lunsford, The St. Martin's Handbook. Bedford, 2008)

  • Generic Number
    "The concept of generic number, which incorporates both singular and plural and is used when one doesn't want to specify number, is expressed in English in three ways:
    1. the definite article + singular noun (The tiger may be dangerous),
    2. the indefinite article + singular noun (A tiger may be dangerous),
    3. Ø article + plural of count nouns or a singular of mass nouns (Tigers may be dangerous or Gold is valuable)."
    (Laurel J. Brinton and Donna M. Brinton, The Linguistic Structure of Modern English. John Benjamins, 2010)


Pronunciation: NUM-ber