The trapezius.
The large muscle at the top of the thigh that covers the hip joint in the posterior is called the gluteus maximus.
The deltoid muscle looks like a large "D" covering the shoulder. There are three parts to it: The anterior deltoid which is commonly called front delts, The lateral deltoids or side delts, and the posterior deltoid or rear delts. The anterior deltoid's (front delts') origin is the clavicle, the lateral's (side delts') origin is the acromion process of the scapula and the posterior's (rear delts') origin is the spine of the scapula. The insertion for all is the deltoid tuberosity on the humerus.
The large posterior process on the scapula is called the acromion process. It forms the bony tip of the shoulder and articulates with the clavicle to form the acromioclavicular joint. The acromion process provides attachment points for various muscles and ligaments involved in shoulder movement.
Trapezius
A pair of large neck muscles called sternocleidomastoids is responsible for turning the head.
The latissimus dorsi muscle is responsible for adducting the shoulder and causing extension of the shoulder joint. It is a large triangular muscle located in the back that helps with various movements of the shoulder and arm.
The muscle between the neck and the shoulder is the trapezius muscle. It is a large, triangular shaped muscle that helps to move and stabilize the shoulder blades and support the neck and head. It is responsible for movements like shrugging the shoulders and tilting and turning the head.
There is one bone that is known by laymen as the shoulder blade and it is called the Scapula. It is a fairly large flat triangular shape that is connected to the posterior of the ribcage by the subscapular muscles.
a large triangular muscle covering the joint of the shoulder, the action of which raises the arm away from the side of the body.
This is, if on the shoulder, probably the deltoid.
The muscle located in the upper part of your back in the middle is called the trapezius muscle. It is a large, triangular muscle that extends from the base of your skull down to the middle of your spine and across to your shoulders. Its primary function is to move and stabilize the shoulder blades.
The Deltoid muscle is a large triangular shaped muscle which lies over the glenohumeral joint and which gives the shoulder its rounded countour, its probably located on the uppermost part of the arm and the top of the shoulder