Nouns with special plural forms

(Irregular plural formation of nouns in English)

Table of contents – nouns with special plural forms

On this page you will find the following:

  1. Nouns with irregular plural forms
  2. Further explanations and exercises

What nouns have irregular plural forms in English (explanation)?

In the English language, there are nouns with regular plural forms as well as nouns with specific ones in the plural which follow irregular patterns. One reason for such irregularities is that many of them have been borrowed from other languages. Compare such nouns with exceptions in the following:

  • Some examples of English nouns that have an irregular plural form. Some of them can also produce two forms – one regular and one irregular:
    • General nouns that do not follow a rule and, therefore, form their plural irregularly:
      • childchildren
      • manmen
      • womanwomen
      • footfeet
      • toothteeth
      • mousemice
      • louselice
      • oxoxen
      • goosegeese or gooses
    • In addition, some nouns have been adopted from other languages (such as Latin or Greek) into English and, as a result, have particular forms. Such words are called loanwords. In some cases, regular forms of them exist, which are marked in green in the following list:
      • basisbases
      • crisiscrises
      • diagnosisdiagnoses
      • formulaformulae
      • oasisoases
      • indexindexes or indices
      • analysisanalyses
      • alumnusalumni
      • phenomenonphenomena
      • curriculumcurricula
      • appendixappendixes or appendices
      • axisaxes
      • thesistheses
      • mediummediums or media
      • criterioncriteria
      • datum* → data
        • *The singular form ‘datum’ is only used in technical jargon.
      • syllabussyllabuses or syllabi
      • cactuscactuses or cacti
      • octopusoctopuses or octopi

Further explanations relating to ‘Nouns with special plural forms’

The following explanations refer to the topic ‘English nouns with irregular plural formation’ and might be helpful: