Aphasia Aphasia () is a language disorder in which there is an impairment (but not loss) of speech and of comprehension of speech. The term dysphasia has also been used, although in modern times aphasia is used much more commonly, particularly in the field of speech and language pathology, to avoid confusion with the swallowing disorder dysphagia.Depending on the area and extent of the damage, someone suffering from aphasia may be able to speak but not write, or vice versa, or display any of a wide variety of other deficiencies in language comprehension and production, such as being able to sing but not speak.