Specialization
Specialization refers to the narrowing of choices that characterizes an emergent grammatical construction. The lexical meaning of a grammaticalizing feature decreases in scope, so that in time the feature conveys a generalized grammatical meaning.
“Within a functional domain, at one stage a variety of forms with different semantic nuances may be possible; as grammaticalization takes place, this variety of formal choices narrows and the smaller number of forms selected assume more general grammatical meanings.” (Hopper 1991: 22)
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