deltoidus

plural deltoidi

1. anatomythe deltoid muscle.

   The muscles involved in the external rotation are: Infraspinatus, Teres minor, Deltoidus and Supraspinatus.

   2013, Mihaela Manisor, Cosmin Marcu, Gheorghe Tomoaia, Liviu Miclea, “Comparison between Titan and Cobalt Hydroxyapatite-Coated Shoulder Prosthesis”, in Advances in Intelligent Control Systems and Computer Science, page 194

   3 more examples

   The deltoid muscle of the human raises the arm. Its anterior section pulls the arm forward and rotates it inward while its posterior section pulls it backward and rotates it outward. The same muscle in the animal, known as the deltoidus, abducts the upper portion of the forelimb and flexes the shoulder.

   1983, Fredric Sweney, The Art of Painting and Drawing Animals, page 37

   The deltoidus is a thick, large triangular muscle that covers the shoulder joint in the front, behind and laterally. It encircles the cap of the shoulder. The muscle fibers converge to unite in a thick tendon which inserts into the middle lateral side of the upper arm bone. The muscle's basic action is to lift the arm away from the body. It makes sense then that forward, lateral, and backward movements are necessary to work the muscle fully. ¶ The trapezius is a flat triangular muscle that covers parts of the neck, shoulders and upper back.

   2012, Arnold Schwarzenegger, Douglas Kent Hall, Arnold: The Education of a Bodybuilder

   Other muscles appear less affected by fatigue in the movement with amplitude increase during the cocking phase for the biceps brachii, and frequency decrease for the extensor digitorum and duration increase for deltoidus during the strike phase.

   2017, Annie Rouard, Thomas Robert, Ludovic Seifert, “Biomechanics of ice tool swinging movement”, in The Science of Climbing and Mountaineering, page 173