Pectoralis major

<p>The pectoralis major  is a thick, fan-shaped or triangular <a href="/facts/Convergent_muscle/Tl6vVdUz">convergent muscle</a> of the human chest. It makes up the bulk of the <a href="/facts/Pectoral_muscles/3UFp0cXN">chest muscles</a> and lies under the <a href="/facts/Breast/UBvcKAjy">breast</a>. Beneath the pectoralis major is the <a href="/facts/Pectoralis_minor/YkMKXSUc">pectoralis minor muscle</a>.
</p><p>The pectoralis major arises from parts of the <a href="/facts/Clavicle/YWNjLv6s">clavicle</a> and <a href="/facts/Sternum/qIPMpyIz">sternum</a>, <a href="/facts/Costal_cartilage/c49rMqFC">costal cartilages</a> of the <a href="/facts/True_rib/KzXLlujq">true ribs</a>, and the <a href="/facts/Aponeurosis/Uhq7UcN4">aponeurosis</a> of the <a href="/facts/Abdominal_external_oblique_muscle/Kw7mhgYT">abdominal external oblique muscle</a>; it inserts onto the lateral lip of the <a href="/facts/Bicipital_groove/jsh2Hhjz">bicipital groove</a>. It receives double motor innervation from the <a href="/facts/Medial_pectoral_nerve/gQJnTIDp">medial pectoral nerve</a> and the <a href="/facts/Lateral_pectoral_nerve/HxEGXJpl">lateral pectoral nerve</a>. The pectoralis major's primary functions are <a href="/facts/Flexion/KmBVfcPk">flexion</a>, <a href="/facts/Adduction/KmBVfcPk">adduction</a>, and <a href="/facts/Internal_rotation/KmBVfcPk">internal rotation</a> of the <a href="/facts/Humerus/9h0R2GuY">humerus</a>. The pectoral major may colloquially be referred to as "pecs", "pectoral muscle", or "chest muscle", because it is the largest and most superficial muscle in the chest area.
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Pectoralis major open-in-new

Pectoralis major