Polysynthetic
Polysynthetic languages are highly inflected languages, i.e. languages in which words are composed of many morphemes. A synthetic language is one that has more than one morpheme per word, and that covers most languages, but a polysynthetic one has a more extreme degree of morpheme joining, and is often taken to mean that there is some degree of incorporation, such as of noun and verb together in the same word. At a minimum, the number, person, and noun class (if present) of both the subject and object are marked on the verb in some way, allowing very free word order.
There are two main ways that words can be built up of many morphemes. Agglutinative languages build words by "gluing" morphemes together essentially unchanged. Fusional languages build words by "squishing" morphemes together, often changing the morphemes in the process. European languages tend to be fusional languages, while Native American languages tend to be highly agglutinative.
Examples of polysynthetic languages include Inuktitut, Mohawk, and numerous other languages of North America and Siberia. Languages with a high degree of synthesis but without being incorporating include Basque and the Bantu languages. According to some linguists, spoken French can be classed as highly synthetic: a phrase such as je ne le sais pas is all one word, with the words that are separate in the standard written language becoming clitics or word inflections in the spoken language. It is structurally similar to a single Bantu word. If this is true, spoken French is thus far and away the most synthetic Indo-European language.
The terms synthetic and polysynthetic in this sense were first used by Edward Sapir in the 1920s.
