Meningitis is an inflammation of the membrane(called the meninges) that surrounds the brain and the spinal column. Meningitis itself doesn't cause deafness, but since the brain is so close to the ears, sometimes the inflammation of the meninges can cause the inner ear to become inflamed also, and this can result in deafness.
well what do ya know? FINALLY I learned exactly how meningitis causes deafness! Ever since I did a project on meningitis in 7th grade, I never really understood exactly how it could cause deafness, and now I do! YAY! I learned something new about ME!