Difference between Meninges and Meninx

What is the difference between Meninges and Meninx?

Meninges as a noun is the three membranes that envelop the brain and spinal cord. while Meninx as a noun is a membrane, especially one of the three membranes enclosing the brain and spinal cord in vertebrates

We hope you now know whether to use Meninges or Meninx in your sentence.