Divergence (linguistics)Divergence in linguistics refers to one of the five principles by which grammaticalization can be detected while it is taking place. The other four are: layering, specialisation, persistence, and de-categorialisation. Divergence names a state of affairs subsequent to some change, namely the result of the process called “split” by Heine and Reh. “When a lexical form undergoes grammaticalization to a clitic or affix, the original form may remain as an autonomous lexical element and undergo the same changes as ordinary lexical items.
Persistence (linguistics)Persistence in linguistics refers to one of the five principles by which grammaticalisation can be detected while it is taking place. The other four are: layering, divergence, specialisation, and de-categorialisation. "When a form undergoes grammaticalization from a lexical to a grammatical function, as long as it is grammatically viable some traces of its original lexical meanings tend to adhere to it, and details of its lexical history may be reflected in constraints on its grammatical distribution.
De-categorializationDe-categorialization (or de-categorialisation) in linguistics refers to one of the five principles by which grammaticalization can be detected while it is taking place (according to Paul Hopper). The other four are layering, divergence, specialization, and persistence. De-categorialization can be described as the loss of morphosyntactic properties.
GrammaticalizationIn historical linguistics, 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 (such as affixes or prepositions). Thus it creates new function words from content words, rather than deriving them from existing bound, inflectional constructions. 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.