psoas muscle Wikipedia:Psoas MA:0002553 BTO:0001140 galen:Psoas uberon psoas SCTID:276167002 EMAPA:36157 NCIT:C33422 MESH:D016658 A powerful flexor of the thigh at the hip joint (psoas major) and a weak flexor of the trunk and lumbar spinal column (psoas minor). Psoas is derived from the Greek 'psoa', the plural meaning 'muscles of the loin'. It is a common site of infection manifesting as abscess (PSOAS ABSCESS). The psoas muscles and their fibers are also used frequently in experiments in muscle physiology. UBERON:0008450 UMLS:C0085221 skeletal muscle organ