deltoids

n. shoulder muscle which raises arm, deltoid muscle (Anatomy); kite, quadrilateral geometrical form having two pairs of equal sides where each pair consists of adjacent sides (Geometry)

In human anatomy, the deltoid muscle is the muscle forming the rounded contour of the shoulder.It was previously called the Deltoideus and the name is still used by some anatomists. It is called so because it is in the shape of the Greek letter Delta (triangle).The deltoid is a frequent site to administer intra-muscular injections.
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Noun
1. a large triangular muscle covering the shoulder joint and serving to abduct and flex and extend and rotate the arm
(synonym) deltoid muscle, musculus deltoideus
(hypernym) skeletal muscle, striated muscle
(part-holonym) rotator cuff
Adjective
1. of a leaf shape; suggesting a capital delta, with a point at the apex
(similar) simple, unsubdivided

DELTOIDI. MUSCOLI DELTOIDI