Home > ADHD Glossary of Terms > CystsPCOSCystsCysts are unusual pockets of fluid that can appear in any part of the body. In the case of PCOS, numerous small fluid-filled sacs form on the outer edge of the ovary, and these are known as cysts.Related termsAcanthosis NigricansAcneAmenorrheaAndrogensAnovulationAnti-Müllerian Hormone (AMH)← Back to full glossary