Subdivision of abdominal segment of trunk which in humans is demarcated from the front of the abdomen by the posterior surface of the anterior layer of the thoracolumbar fascia and the anterior surface of the lumbar vertebral column; together with the front of the abdomen, it constitutes the abdomen[Modified from FMA]. [ FMA:61681 ]
Synonyms: back of abdomen lumbar region of back lower back regio lumbalis abdominal back dorsum of abdomen lumbar part of back posterior part of abdomen