vitreous
This is the fluid that fills the back of the eye. The eye is mostly a hollow structure. The large back chamber is filled with vitreous humor, which is a fluid that has the consistency of Jell-O. In fact, if you were to “theoretically” open up a young person’s eye and remove the contents, the vitreous would come out as a single glob of clear “goop.” As we get older, the vitreous begins to liquefy, with pockets of saline water forming inside the gel. At some point in our life, the mixture gets so watery that the remaining gel will contract inwards upon itself and cause flashes, floaters, and sometimes a retinal detachment. This contraction event is common and called a vitreous detachment.