Formation of compounds

Compound formation rules vary widely across language types.

In a perfectly analytic language, compounds are simply elements strung together without any markers. In English, for example, science fiction is a compound noun that consists of two nouns and no markers. A corresponding example from the Chinese language would be Hànyǔ (漢語; simplified: 汉语), or "the Han Chinese language", which also consists of two nouns and no markers.

In a more synthetic language, the relationship between the elements of a compound may be marked. In German, for example, the compound Kapitänspatent consists of the lexemes Kapitän 'sea captain' and Patent 'license' joined by the genitive case marker -s. In the Latin language, the lexeme paterfamilias contains the (archaic) genitive form familias of the lexeme familia 'family'.

Agglutinative languages tend to create very long words with derivational morphemes. Compounds may or may not require the use of derivational morphemes also. The well-known Japanese compound 神風 kamikaze consists only of the nouns kami 'god, spirit' and kaze 'wind'. The longest compounds in the world may be found in Finnish and Germanic languages, such as Swedish. German examples include Kontaktlinsenverträglichkeitstest 'contact-lens compatibility test' and the jocular Rheindampfschifffahrtsgesellschaftskapitänsstellvertreter 'Rhine steamship-company vice-captain'. In theory, even longer compounds are possible, but they are usually not found in actual discourse.

Compounds can be rather long when translating technical documents from English to, for example, Swedish. "Motion estimation search range settings" can be directly translated to rörelseuppskattningssökningsrymdsinställning; the length of the word is theoretically unlimited.