The term RELATING TO THE EYE can be summarized by two crossword solutions: OPTIC (5 letters) and OCULAR (6 letters). OPTIC refers to the eye's ability to receive light and convert it into electrical signals that are sent to the brain. OCULAR refers to the structures of the eye, such as the cornea, lens, and retina, which are responsible for focusing light and forming an image. Both terms are related to the anatomy and physiology of the eye.