Med-Psych RN ??

I graduate in December and I am considering psych nusing. LOVED my psych roation and had an incredible instructor. (Even though I had started this journey with NICU in mind, after my rotation in the NICU, I realized I was not ready for this) I recently saw a job posting for a med-psych RN position. Can anyone give me some information on this type of position. I have never heard of it before. Thanks for any info anyone can give me.