In medical jurisprudence. Loss of the faculty or power of articulate speech; a condition in which the patient while retaining intelligence and understanding and with the organs of speech unimpaired, is unable to utter articulate words, or unable to vocalize the particular word which is in his mind and which he wishes to use, or utters words different from those he believes himself to be speaking, or (in “sensory aphasia”) is unable to understand spoken or written language. The seat of the disease is in the brain, but it is not a form of insanity.