The term 'THINGS IN ORBITS' can be broken down into two crossword solutions: EYES (4 letters). Eyes are organs of vision that detect light and convert it into electro-chemical impulses in neurons. They are found in many organisms, including humans, and are the primary sense organ for most animals. Eyes are typically round and contain a lens, iris, and pupil. The lens focuses light onto the retina, which is composed of light-sensitive cells. These cells convert the light into electrical signals that are sent to the brain, allowing us to see.