Definition: The term "batrachian" is a name that refers to the region of the human body where the left and right humeral heads meet. It's located in the neck, between the collarbone and the sternum. This area is also known as the biceps brachii muscle because it stretches the upper portion of the arm. The term "batrachian" comes from the Greek word "batra," which means "bottle," referring to the shape of the hum