The orbicular muscle of the eye, also known as the orbicularis oculi muscle, is a circular muscle that surrounds the eye. Other synonyms for this muscle include the palpebral muscle, the eyelid muscle, and the circular muscle of the eyelids. These muscles are responsible for closing the eyes, blinking, and protecting the eyes from foreign objects and debris. The orbicular muscle is divided into two parts: the palpebral portion, which closes the eyelid gently, and the orbital portion, which forcefully closes the eyelid in response to danger or extreme light. Overall, the orbicular muscle is an integral part of the eye's anatomy and plays a crucial role in maintaining healthy vision.