What is the term for the ceaseless occurrence of involuntary muscular movements of the limbs or facial muscles?

The term that best describes the ceaseless occurrence of involuntary muscular movements of the limbs or facial muscles is chorea. Chorea is characterized by quick, irregular, and uncontrollable movements that can affect various parts of the body, making it distinctive from other movement disorders. These movements are often described as dance-like due to their fluidity and unpredictability, which is where the term "chorea," derived from the Greek word for dance, originates.

Dystonia, another movement disorder, involves sustained or repetitive muscle contractions, resulting in twisting and abnormal postures but does not typically encompass the rapid, erratic motions seen in chorea. Myoclonus refers to sudden, brief, shock-like jerks of muscles, which are not continuous and differ significantly in nature from the ceaseless movements of chorea. Tremors usually involve rhythmic shaking movements and are often associated with conditions like Parkinson's disease, rather than the irregular, flowing movements characteristic of chorea. Therefore, the defining nature of chorea makes it the most appropriate and accurate term for the described involuntary movements.