July 26, 2016
font size

Definition of Muscle, psoas

Muscle, psoas: Muscles of the lower back (the loin). There are two psoas muscles on each side of the back. The larger of the two is called the psoas major and the smaller the psoas minor.

The psoas major originates at the spine around the bottom of the rib cage and runs down to the thigh bone (the femur). The psoas major acts to flex the hip.

The psoas minor also originates at the spine around the bottom of the rib cage but it runs down to the bony pelvis. It acts to flex the lower (lumbar) spine.

The "p" in "psoas" is silent and the emphasis is on the first syllable: so-as. The word "psoas" is Greek for the loins, the muscles of the lower back.

Source: MedTerms™ Medical Dictionary
Last Editorial Review: 6/14/2012

Drug Medical Dictionary of Terms by Letter

Top RxList Drug News

Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations