Plural of nouns

The plural suffixes

The table in the preceding section shows the suffixes of cases in plural as combined suffixes. They can mostly be divided into a plural suffix and a case suffix, where the case suffix is the same as in singular, with some exceptions.

Finnish nouns have four different plural suffixes:

• -t in the nominative, not followed by any case suffix, e.g. talo|t
• -i- in most case forms; example: talo|i|ssa
• -j- as the consonant counterpart of -i- between vowels, in the partitive and in the genitive, e.g. talo|j|a, talo|j|en
• – (no suffix) in the genitive plural when
  • the case suffix is -ten, as in lapsi : las|ten (child); although the suffix might be divided into plural suffix -t- and genitive suffix -en, this is not common in grammars
  • the inflection stem ends with i, as in lasi : lasi|en; this could alternatively be described as las|i|en, so that the i is the plural suffix and the i of the stem is lost before it, but this is less natural

The -t suffix in the nominative is dropped when a possessive suffix is appended. Since possessive suffix also causes the strong grade to be used in consonant gradation, the difference between singular and plural is lost in the nominative when a possessive suffix is used. For example, talo and talot both become taloni, when the 1st person singular possessive suffix is added, and similarly lakki and lakit both become lakkini.

The plural stem

Plural forms with -i- as plural suffix are said to consist of a plural stem followed by the case suffix. For example, the plural stem of talo is taloi, and the plural stem of kala is kaloi, appearing in forms like kaloissa and kaloille.

As the latter example shows, the plural stem is not necessarily just the inflection stem used in singular followed by i. There are several different changes in stem before an i suffix. Examples of types of variation: puu : pui-, tie : tei-, hai : hai-, (lapsi :) lapse- : lapsi-, filmi : filmei-, kolea : kolei-, syvä : syvi-, tekijä : tekijöi-, kova : kovi-, vahva : vahvoi-.

For words ending with a diphthong ai, ei, oi in the singular stem, the plural stem is the same as singular stem. E.g., hailla can be either singular or plural form of hai (shark). Plural forms of such words are generally avoided; instead of hai, we can use the compound haikala (“shark-fish”), with singular forms like haikalalla and plural forms like haikaloilla.

Plural forms of loanwords

Finnish does not use foreign plural forms for loanwords the same way as we may use in English for words of Latin or Greek origin. For example, Finnish has kaktus : kaktukse|t (cactus : cacti), so that the loanword has been adapted to the inflection patterns of old Finnish words.

Some loanwords are based on plural forms in other languages but have singular meaning, e.g. fakta (fact, from Latin plural “facta” of “factum”), muffinsi (muffin). They take normal plural suffixes in Finnish, e.g. faktat : faktoja, muffinsit : muffinseja. This has sometimes been criticized as being “double plural”, and forms such as faktumi and muffini have been proposed, without much success.

Use of plural

The use of plural versus singular is described in chapter Singular and plural of noun-like words.