palsy

Palsy is a term for paralysis, weakness, trembling, or poor control of movement, usually caused by trouble in the nervous system. It does not name one single disease. Instead, it can describe a symptom, a state of impaired movement, or appear as part of the name of a medical condition. In most modern contexts, it points to problems involving the brain, spinal cord, nerves, or sometimes the muscles they control.

The word appears in several well-known medical names. Cerebral palsy refers to a group of movement disorders caused by early brain injury or abnormal brain development, often before or during birth. Bell's palsy refers to sudden, usually temporary weakness or paralysis on one side of the face. In these names, the word keeps its core idea of impaired muscle control, even though the causes and symptoms differ.

Historically, "palsy" was used more generally to describe trembling or weakness of many kinds, including shaking linked with fear, age, or illness. In older literature, a person might be said to have a palsy simply because their hands shook or their body seemed weak. That older use still appears in classic writing, but in present-day English the word is mainly heard in medical contexts.

So if you see "palsy" on its own, think of a loss of normal muscle control: paralysis, weakness, or shaking. If you see it in a longer name, the exact meaning depends on the condition being described. The word has an old literary life and a modern medical one, but both uses share the same central picture: the body is no longer moving with its usual strength or steadiness.