Definition of effusion

• n. - The act of pouring out; as, effusion of water, of blood, of grace, of words, and the like.
• n. - That which is poured out, literally or figuratively.
• n. - The escape of a fluid out of its natural vessel, either by rupture of the vessel, or by exudation through its walls. It may pass into the substance of an organ, or issue upon a free surface.
• n. - The liquid escaping or exuded.