The protective membranes that surround your brain and spinal cord are called meninges. Your meninges do an important job — helping to keep your nervous system safe from harm.
The illness known as meningitis is an inflammation of the meninges that's caused by a viral or bacterial infection. This condition can be serious because of how close the brain is to the meninges and how vital they are for protecting it. The Greek root, meninx, means "membrane."