the watery fluid that fills the anterior and posterior chambers of the eye. It is secreted by the ciliary processes within the posterior chambers and passes through the the pupil into the anterior chamber where it filters through the trabecular meshwork and is reabsorbed into the venous system at the iridocorneal angle by way of the sinus venosus of the sclera; Syn: humor aquosus [NA], intraocular fluid.