Morphological typology is a way of classifying languages (see linguistic typology) that groups languages according to their morphological structures. The field organizes languages on the basis of how those languages form words by combining morphemes (parts of words). Two primary categories exist to distinguish all languages: analytic languages and synthetic languages, where each term refers to the opposite end of a continuous scale including all the world's languages.
Analytic languages have a low ratio of morphemes to words; in fact, the correspondence is nearly one-to-one. Sentences in analytic languages are composed of independent morphemes and standalone roots. Grammatical relations between words are expressed by separate word where they might otherwise be expressed by affixes, which are present to a minimal degree in such languages. There is little to no changes in the morphology words: they tend to be uninflected. Grammatical categories are indicated by word order (for example, inversion of verb and subject for interrogative sentences) or by bringing in additional words (for example, a word for "some" or "many" instead of a plural inflection like English -s). Individual words carry a general meaning (root concept); nuances are expressed by other words. Finally, in analytic languages context and syntax are more important than morphology.
Analytic languages include some of the major East Asian languages, such as Chinese, and Vietnamese. Additionally, English is moderately analytic (probably one of the most analytic of Indo-European languages). However, it is traditionally analyzed as a synthetic language.
Synthetic languages form words by affixing a given number of dependent morphemes to a root morpheme. The morphemes may be distinguishable from the root, or they may not. They may be fused with it or among themselves (in that multiple pieces of grammatical information may potentially be packed into one morpheme). Word order is less important for these languages than it is for analytic languages, since individual words express the grammatical relations that would otherwise be indicated by syntax. In addition, there tends to be a high degree of concordance (agreement, or cross-reference between different parts of the sentence). Therefore, morphology in synthetic languages is more important than syntax. Most Indo-European languages are moderately synthetic.
There are two subtypes of synthesis, according to whether morphemes are clearly differentiable or not. These subtypes are agglutinative and fusional (or inflectional or flectional in older terminology).
Agglutinative languages have words containing several morphemes that are always clearly differentiable from one another in that each morpheme represents only one grammatical meaning and the boundaries between those morphemes are easily demarcated; that is, the bound morphemes are affixes, and they may be individually identified. Agglutinative languages tend to have a high number of morphemes per word, and their morphology is highly regular.
Morphemes in fusional languages are not often distinguishable from the root or among themselves. Several grammatical bits of meaning may be fused into one affix. Morphemes may also be expressed by internal phonological changes in the root (i.e. morphophonology), such as consonant gradation and vowel gradation, or by suprasegmental features such as stress or tone, which are of course inseparable from the root.
In 1836, Wilhelm von Humboldt proposed a third category for classifying languages, a category that he named polysynthetic. (The term polysynthesis was first used in linguistics by Peter Stephen DuPonceau who borrowed it from chemistry.) These languages have a high morpheme-to-word ratio, a highly regular morphology, and a tendency for verb forms to include morphemes that refer to several arguments besides the subject (polypersonalism). Another feature of polysynthetic languages is commonly expressed as "the ability to form words that are equivalent to whole sentences in other languages". Of course, this is rather useless as a defining feature, since it is tautological ("other languages" can only be defined by opposition to polysynthetic ones, and vice versa).
Many Amerindian languages are polysynthetic. Inuktitut is one example, for instance the word-phrase: tavvakiqutiqarpiit roughly translates to "Do you have any tobacco for sale?".
Note that no clear division exists between synthetic languages and polysynthetic languages; the place of one language largely depends on its relation to other languages displaying similar characteristics on the same scale.
Morphological typology in realityEdit
Each of the types above are on opposite ends of a spectrum; they do not exist in a pure state in reality. Although they generally fit best into one category, all languages are mixed types. English is not analytic, but it is more analytic than Spanish, and much more analytic than Latin. Chinese is the usual model of analytic languages, but it does have some bound morphemes. Japanese is highly synthetic (agglutinative) in its verbs, but clearly analytic in its nouns. For these reasons, the scale above is continuous and gradual, and not absolute. It is difficult to classify a language as absolutely analytic or synthetic, as a language could be described as more synthetic than Chinese, but less synthetic than Korean.