intraocular pressure

pressure within the eye caused by fluid in the orbit

Intraocular pressure (IOP) is the fluid pressure inside the eye.
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Intraocular pressure n. The pressure of the intraocular fluid within the eye. intraocular pressure, n the internal pressure of the eye, regulated by [more]Intraocular pressure - Community and Resources

Noun
1. pressure inside the eyeball;regulated by resistance to the outward flow of aqueous humor; "glaucoma results from increased intraocular pressure"
(hypernym) pressure, pressure level, force per unit area