Final answer:
Meningiomas are benign tumors that originate in the dura mater, the protective outer layer of the meninges around the brain and spinal cord.
Step-by-step explanation:
Meningiomas are benign tumors that originate in the dura, which is one of the three layers of the meninges designed to protect the brain and spinal cord. The dura is the outermost layer and provides a strong protective sheath over the entire brain and spinal cord.
The other meningeal layers include the arachnoid mater and the pia mater. Meningiomas can cause symptoms by compressing nearby brain structures as they grow, and though they are usually benign, they can sometimes behave more aggressively or become malignant.