Orbicularis oris is a muscle in the human face that is responsible for puckering, closing, and shaping the lips. It is also known as the "orbicular muscle" or "kissing muscle". Other synonyms for orbicularis oris include "circum-oral muscle" as it surrounds the mouth, "musculus orbicularis thesauri marcionis" which refers to its placement in the face, and "musculus sphincter oris" for its sphincter-like action in closing the mouth. The orbicularis oris plays an important role in facial expressions, speech, and even in playing musical instruments like the trumpet. It is a fascinating muscle that is essential to our daily lives and communication.