Chapter 23 reviews the role of grammaticalization at different levels of grammar: phonological, morpho-syntactic, paradigmatic, and semantic-pragmatic. It first discusses the dischronic principles and mechanisms that have been proposed in previous grammaticalization studies. The chapter then examines the prominent patterns by source category, dividing these into nouns and verbs. In the nominal category, four source construction types are illustrated with the reanalyses that led to their emergence as grammatical forms such as postpositions, conjunctions, and auxiliaries. In the verbal category, four source construction types are illustrated, with special focus on the grammaticalization of de-verbal postpositions and auxiliary verbs. The chapter further addresses select aspects of Korean grammaticalization from a typological perspective. It discusses the productive use of affixes, converbs, and predicatives known as “mermaid constructions”, which are among the characteristics shared by many languages in the eastern Eurasian region. It also discusses the presence of large inventories of de-verbal postpositions and numeral classifiers.

In the course of the last decades, a wealth of data has been published on the origin and development of grammatical forms. Part of these data, as they were available up to 2002, were published in the first edition of the World Lexicon of Grammaticalization. The main purpose of the present work is, first, to make some revisions to the first edition and, second, to provide an update on some of what has happened in grammaticalization studies since 2002. The update concerns, on the one hand, new, general developments that this field has experienced. To this end, some of the directions that appear to be particularly relevant to the field are pointed out in Section 1.3. On the other hand, the update concerns a wider database, considerably expanded with regard to the distinct language varieties (i.e. dialects included), which are over 1,000, and the processes discussed, which involve 544 grammaticalization paths.

This pathway appears to be based on a conceptualization of agents as sources of actions (see Luraghi 2014). According to Palancar (2002: 205), ablatives form by far the most common spatial category found in the syncretism of passive agent markers. While the present pathway may provide a natural choice in any language, it has been exploited especially but not only in Indo-European languages. In languages showing this pathway, ablative or source markers (‘(away) from’) gradually develop into markers encoding agent participants (see Palancar 2002: 205, table 7; Wiemer 2011a: 541) as shown in the following two examples.

Archaic Chinese yu ‘from’, ablative preposition (> switch stage, either ablative or agent marker) > yu, preposition introducing agents (Long et al. 2012). Modern Chinese you ‘from’, ablative preposition (> cause marker) > you, preposition introducing agents (Long et al. 2012). Qiang -wu, ablative postposition > -wu, agent postposition (Long et al. 2012).