Which muscle is also referred to as the depressor muscle, known as the "Depressor Angulus Oris"?

The muscle known as the depressor muscle, referred to as the "Depressor Angulus Oris," is the Triangularis. This muscle plays a crucial role in facial expressions, particularly in lowering the corners of the mouth. Its action is essential for conveying emotions such as sadness or disapproval.

The Triangularis originates from the mandible and inserts into the skin at the corner of the mouth. When it contracts, it pulls the corners of the mouth downward, effectively creating a frown. Understanding the function of this muscle is important in the study of anatomy and in fields related to facial aesthetics and expressions.

In contrast, the other muscles listed have different primary functions. The Masseter is a major muscle involved in chewing and elevating the jaw. The Buccinator is primarily responsible for chewing and helping to keep food within the cheeks while eating. The Zygomaticus muscles assist in elevating the corners of the mouth, thus facilitating smiling. These distinct roles highlight the specialized function of the Triangularis as the depressor muscle in facial anatomy.