Grammaticalisation

In historical linguistics and language change, grammaticalization (also known as grammatization or grammaticization) is a process of language change by which words representing objects and actions (i.e. nouns and verbs) become grammatical markers (affixes, prepositions, etc.). Grammaticalization creates new function words by a process other than deriving them from existing bound, inflectional constructions, instead deriving them from content words. For example, the Old English verb willan 'to want', 'to wish' has become the Modern English auxiliary verb will, which expresses intention or simply futurity. Some concepts are grammaticalized in most languages, such as tense, negation, or number, while others, such as evidentiality are rare.

For an understanding of this process, a distinction needs to be made between lexical items, or content words, which carry specific lexical meaning, and grammatical items, or function words, with little or no lexical meaning, which serve to express grammatical relationships between the different words in an utterance. Grammaticalization has been defined as "the change whereby lexical items and constructions come in certain linguistic contexts to serve grammatical functions, and, once grammaticalized, continue to develop new grammatical functions". Simply said, grammaticalization is the process in which a lexical word or a word cluster loses some or all of its lexical meaning and starts to fulfil a more grammatical function. Where grammaticalization takes place, nouns and verbs which carry certain lexical meaning develop over time into grammatical items such as auxiliaries, case markers, inflections, and sentence connectives.

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