Fusional languages or inflected languages are a type of synthetic language, distinguished from agglutinative languages by their tendency to use a single inflectional morpheme to denote multiple grammatical, syntactic, or semantic features.
For example, the Spanish verb comer ("to eat") has the first-person singular preterite tense form comí ("I ate"); the single suffix -í represents both the features of first-person singular agreement and preterite tense, instead of having a separate affix for each feature.
Another illustration of fusionality is the Latin word bonus ("good"). The ending -us denotes masculine gender, nominative case, and singular number. Changing any one of these features requires replacing the suffix -us with a different one. In the form bonum, the ending -um denotes masculine accusative singular, neuter accusative singular, or neuter nominative singular.
Examples of fusional Indo-European languages include the Balto-Slavic languages, such as Polish, Russian, Ukrainian and South Slavic languages (with the exception of Bulgarian and Macedonian, which are partially analytic); Sanskrit, Pashto, modern Indo-Aryan languages (such as Persian, Hindustani, Kashmiri, and Punjabi); Greek (Classical and Modern), Latin, Italian, French, Spanish, Portuguese and Romanian; Irish, Welsh, German, Faroese, Icelandic and Albanian.
Northeast Caucasian languages are weakly fusional.
Ya k-tįmi x-įnn nį-y ya.
1P REL-land go-CERT.MASC PRES-MASC 1P
'I go to my land.'
Loss of fusionality
Fusional languages generally tend to lose their inflection over the centuries, some much more quickly than others. Proto-Indo-European was fusional, but some of its descendants have shifted to a more analytic structure such as Modern English, Danish and Afrikaans or to agglutinative such as Persian and Armenian.
Gain of fusionality
Some languages shift over time from agglutinative to fusional.
For example, most Uralic languages are predominantly agglutinative, but Estonian is markedly evolving in the direction of a fusional language. On the other hand, Finnish, its close relative, exhibits fewer fusional traits and thereby has stayed closer to the mainstream Uralic type. However, Sámi languages, while also part of the Uralic family, have gained more fusionality than Finnish and Estonian since they involve consonant gradation but also vowel apophony.
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One feature of many fusional languages is their systems of declensions in which nouns and adjectives have a suffix attached to them that specifies grammatical case (their uses in the clause), number and grammatical gender. Pronouns may also alter their forms entirely to encode that information.
Within a fusional language, there are usually more than one declension; Latin and Greek have five, and the Slavic languages have anywhere between three and seven. German has multiple declensions based on the vowel or consonant ending the word, they can often be unpredictable.
However, many descendants of fusional languages tend to lose their case marking. In most Romance and Germanic languages, including Modern English (with the notable exceptions of German and Icelandic), encoding for case is merely vestigial because it no longer encompasses nouns and adjectives but only pronouns.
Compare the Italian egli (masculine singular nominative), gli (masculine singular dative, or indirect object), lo (masculine singular accusative) and lui (also masculine singular accusative but emphatic and indirect case to be used with prepositions), corresponding to the single vestigial pair he, him in English.
Conjugation is the alteration of the form of a verb to encode information about some or all of grammatical mood, voice, tense, aspect, person, grammatical gender and number. In a fusional language, two or more of those pieces of information may be conveyed in a single morpheme, typically a suffix.
For example, in French, the verbal suffix depends on the mood, tense and aspect of the verb, as well as on the person and number (but not the gender) of its subject. That gives rise to typically 45 different single-word forms of the verb, each of which conveys some or all of the following:
- mood (indicative, subjunctive, conditional or imperative)
- tense (past, present or future)
- aspect (perfective or imperfective)
- person (first, second or third), and
- number (singular or plural).
Changing any one of those pieces of information without changing the others requires the use of a different suffix, the key characteristic of fusionality.
English has two examples of conjugational fusion. The verbal suffix -s indicates a combination of present tense with both third-person and singularity of the associated subject, and the verbal suffix -ed used in a verb with no auxiliary verb conveys both non-progressive aspect and past tense.
- See pp. 50–51 in Zuckermann, Ghil'ad (2009), "Hybridity versus Revivability: Multiple Causation, Forms and Patterns", Journal of Language Contact, Varia 2, pp. 40–67.
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