Clinical linguistics is the application of the linguistic sciences to the study of language disability in all its forms. Conceived as a “pure” subject, clinical linguistics is analogous to the goal of “pure linguistics.” A commonly stated aim of linguistics is to define the notion of human language, characterized by a set of linguistic universals. The long-term aim of clinical linguistics is to define the notion of human language disability in a similar way.

The label disability should not be too narrowly interpreted. In clinical linguistics, the word relates to anyone whose ability to use language is sufficiently undeveloped or impaired as to require special treatment or teaching—whether or not that person attends a clinic in a doctor’s office or a hospital. It is one of ...