lumbar plexus

Main Entry: lumbar plexus
Function: noun
: a plexus embedded in the psoas major and formed by the anterior or ventral divisions of the four upper lumbar nerves of whichthe first is usually supplemented by a communication from the twelfth thoracic nerve

lumbar plexus n.

1. A nerve plexus formed by the ventral branches of the first four lumbar nerves and lying in the substance of the psoas muscle.

2. A lymphatic plexus formed of about twenty lymph nodes and connecting vessels situated along the aorta and the common iliac vessels.