Antonyms are words that have opposite meanings to one another. Therefore, antonyms for "Cranial Nerve XI Diseases," which refers to a group of medical conditions that affect the spinal accessory nerve, may include terms related to good health, wellness, absence of disease, normal function, and vitality. Some examples of antonyms that come to mind are fitness, strength, vitality, healthiness, wellness, normality, and absence of neurological symptoms. While these terms may not be directly related to the spinal accessory nerve or its functions, they represent positive and healthy states of being that are the opposite of the pathological conditions that affect the nerve.