The term SIGHT PART is related to the anatomy of the eye and can be defined as the part of the eye that focuses light onto the retina. The crossword solution for this term is LENS, which is a transparent structure that helps to focus light rays onto the retina. The LENS is made up of proteins and water and is located behind the iris and pupil. It is responsible for focusing light onto the retina, which then sends signals to the brain, allowing us to see.