muscle

The pectoralis major muscle is a broad and triangular muscle with origins on the clavicle, sternum, ribs, and external oblique fascia that acts as an adductor, flexor, and internal rotator of the humerus [1-17].

Then in quick succession, we add the smiling muscles, levator anguli oris (attaching just below the eye to lift the corners of the mouth) and the sadness muscles, levator labii superioris (Fig 4) (which deepen the nasiolabial fold when crying or being serious) and the depressor anguli oris, the disgust muscle (a triangular muscle attaching to the lower jaw at the side of the mouth) which lowers the corners of the mouth.

The deltoid is a triangular muscle composed of the anterior, medial, and posterior portions and can generate great torque at the shoulder (11), (12).

Yeah Man is a big-name casualty in the final heat after sustaining a torn triangular muscle in the opening round.

DELTOID The deltoid is a rounded, triangular muscle located on the uppermost part of the arm and the top of the shoulder.