Internal borrowing

Definition
Internal borrowing describes a process of borrowing in which a word is copied from a non-standard variety into the standard language (cf. Görlach 2001: 158). For lack of prestige, dialect words are often not considered dictionary-worthy, but eventually some items may become fully integrated in the standard variety, typically without the speakers being aware of their origin.

Example
The (now standard) English word clever derives from the East Anglian dialect word cliver (c 1590), which meant 'expert at seizing'. The extended meaning of clever in contemporary standard English is first attested in 1704.

Literature
Görlach, Manfred (2001, Eighteenth-Century English, Heidelberg: Winter.