lumbar node, a node in one of the seven groups of parietal lymph nodes serving the abdomen and the pelvis. The lumbar nodes are numerous and are divided into the lateral aortic nodes, preaortic nodes, and retroaortic nodes. They receive the afferent vessels from many different structures, such as the kidneys, the internal reproductive organs, the lateral abdominal muscles, and certain vertebrae, and pass efferents that form lymphatic trunks. Compare sacral node. See also lymph, lymphatic system, lymph node.
