Agglutinative language

Agglutinative language
An agglutinative language is a type of synthetic language with morphology that primarily uses agglutination. In an agglutinative language, words contain multiple morphemes concatenated together, but in such a manner that individual word stems and affixes can be isolated and identified as to indicate a particular inflection or derivation, although this is not a rule: for example, Finnish is a typical agglutinative language, but morphemes are subject to (sometimes unpredictable) consonant alternations called consonant gradation.
Despite the occasional outliers, agglutinative languages tend to have more easily deducible word meanings compared to fusional languages, which allow unpredictable modifications in either or both the phonetics or spelling of one or more morphemes within a word, usually resulting from a shortening of the word or to make pronunciation easier.
Overview
Agglutinative languages have generally one grammatical category per affix while fusional languages combine multiple into one. The term was introduced by Wilhelm von Humboldt to classify languages from a morphological point of view. It is derived from the Latin verb agglutinare, which means "to glue together". For example, the English word antidisestablishmentarianism can be broken up into anti- "against", dis- "to deprive of", establish (here referring to the formation of the Church of England), -ment "the act of", -arian "a person who", and -ism "the ideology of". On the other hand, in a word such as runs, the singular suffix -s indicates the verb is both in third person and present tense, and cannot be further broken down into a "third person" morpheme and a "present tense" morpheme; this behavior is reminiscent of fusional languages.
The term agglutinative is sometimes incorrectly used as a synonym for synthetic, but that term also includes fusional languages. The agglutinative and fusional languages are two ends of a continuum, with various languages falling more toward one or the other end. For example, Japanese is generally agglutinative, but displays fusion in some nouns, such as , from oto + hito (originally woto + pito, "young, younger" + "person"), and Japanese verbs, adjectives, the copula, and their affixes undergo sound transformations. For example, affixed with and becomes . A synthetic language may use morphological agglutination combined with partial usage of fusional features, for example in its case system (e.g., German, Dutch, and Persian).
Agglutinative languages tend to have a high rate of affixes or morphemes per word, and to be very regular, in particular with very few irregular verbs - for example, Japanese has only two considered fully irregular, and only about a dozen others with only minor irregularity; Luganda has only one (or two, depending on how "irregular" is defined); while in the Quechua languages, all ordinary verbs are regular. Again, exceptions exist, such as in Georgian and Korean.
Trends
Many unrelated languages spoken by Ancient Near East peoples were agglutinative, though none from larger families have been identified:
Elamite
Hattic
Kassite
Lullubi
Sumerian language
Some well known constructed languages are agglutinative, such as Black Speech, Esperanto, Klingon, and Quenya.
Agglutination is a typological feature and does not imply a linguistic relation, but there are some families of agglutinative languages. For example, the Proto-Uralic language, the ancestor of the Uralic languages, was agglutinative, and most descendant languages inherit this feature. But since agglutination can arise in languages that previously had a non-agglutinative typology, and it can be lost in languages that previously were agglutinative, agglutination as a typological trait cannot be used as evidence of a genetic relationship to other agglutinative languages. The uncertain theory about Ural-Altaic proffers that there is a genetic relationship with this proto-language as seen in Finnish, Mongolian and Turkish.
Many languages have developed agglutination. This developmental phenomenon is known as language drift. There seems to exist a preferred evolutionary direction from agglutinative synthetic languages to fusional synthetic languages, and then to non-synthetic languages, which in their turn evolve into isolating languages and from there again into agglutinative synthetic languages. However, this is just a trend, and in itself a combination of the trend observable in grammaticalization theory and that of general linguistic attrition, especially word-final apocope and elision.
References
Citations
Sources
Bodmer, Frederick. Ed. by Lancelot Hogben. The Loom of Language. New York, W.W. Norton and Co., 1944, renewed 1972, pages 53, 190ff. .
Synthetic languages