Question: lies between the arachnoid mater and pia mater and is filled with cerebrospinal fluid
Answer: The meninges ( / məˈnɪndʒiːz / , singular : meninx ( / ˈmiːnɪŋks / or / ˈmɛnɪŋks / ) , from Ancient Greek : μῆνιγξ , translit .