psoas major (muscle)


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pso·as ma·jor (mus·cle)

[TA]
groin muscle; origin, bodies of vertebrae and intervertebral discs from the twelfth thoracic to the fifth lumbar, and transverse processes of the lumbar vertebrae; insertion, forms a common insertion with iliacus muscle into lesser trochanter of femur; action, primary flexor of hip joint; nerve supply, lumbar plexus (ventral rami of first, second and usually third lumbar spinal nerves).