Can "dyslexia of the mouth" be a real disorder?

There is no medical: or psychiatric disorder by that name. Dyslexia = reading disorder. It is language-based in 90% of cases. Perhaps someone used it as a euphemism for aphasia, specific language impairment or other neurologically-based difficulties impacting language comprehension &/or production, depending on the age of the patient & the underlying medical or mental illness.