the process by which new grammatical constructions emerge from novel and specialized uses of other grammatical constructions; once a grammatical construction acquires a novel, specialized function, it eventually undergoes changes in morphosyntactic structure and scope, and often also phonetic form. Example: a kind of originally expressed a type of object, then shifted meaning to become a hedging phrase for a less-central member of a category, was extended to describe hedging of a property word (kind of cute), and was phonetically reduced to kinda. (Sections 1.1, 2.3)