Abstract
This paper starts by defining a typical case of grammaticalization (or grammaticization) as a process whereby independent lexical items become dependent forms and acquire grammatical functions, and provides a set of criteria for characterizing this process. They are: abstractness of meaning, paradigmaticity, obligatoriness of marking, morphological boundedness, and interaction with the rest of grammar. Further, extended cases of grammaticalization are discussed, namely the rise of polyfunctionality and the emergence of grammatical constructions. It is shown that, especially in the latter, discourse function plays a crucial role in the conventionalization of a syntagm into a grammatical construction. In the last section, some considerations are given to the motivation behind grammaticalization. Two major forces are metaphor (i.e. cross-domain mapping) and metonymy (i.e. domaininternal profile shift). Finally, general constraints on semantic change are discussed.
