1. Loss of the ability to write, resulting from neurological damage such as a brain lesion: After Mable's severe head injury, she experienced agraphia and so she was incapable of communicating with a pen or a pencil.
2. Being incapable of writing properly which can be a result of aphasia and alexia that is caused by lesions in various portions of the cerebrum; especially, those in or near the angular gyrus of the brain or that part of the brain that is involved in the processing of auditory and visual input and in the comprehension of language: After many medical examinations, the doctors determined that the agraphia experienced by Bryant was neurologically different from that which might have resulted from an injured arm.

The inability to write from dictation or from what is heard: Dr. Davis is a specialist in treating acoustic agraphias with which several of his patients are afflicted.