aqueous
Meaning of aqueous: Aqueous describes a solution, fluid, or preparation that is water-based, distinguishing it from oil-based or alcohol-based alternatives.
Definition of aqueous
Aqueous means relating to, containing, or dissolved in water. The term is used to describe solutions and preparations, such as an aqueous medication solution, as well as body fluids, such as the aqueous humor, the clear fluid that fills the front chamber of the eye between the cornea and the lens.
In pharmacy and laboratory contexts, describing a preparation as aqueous distinguishes it from oil-based, alcohol-based, or other non-water solvents, which can affect how a substance is absorbed, stored, or administered. In anatomy and physiology, aqueous fluids are distinguished from other body fluids by their composition and the specific role they serve.
The aqueous humor of the eye, for example, helps maintain intraocular pressure and supplies nutrients to structures that lack their own blood supply.
Used in a sentence
The ophthalmologist measured the flow of aqueous humor as part of the glaucoma evaluation.
Good to know
Aqueous humor should not be confused with vitreous humor; the aqueous humor fills the front of the eye and is continuously produced and drained, while the vitreous humor is the thicker gel filling the back chamber.
Word origin
Where “aqueous” comes from
From Latin aqua, meaning "water."