Source : Webster's Revised Unabridged Dictionary (1913)

Effusion \Ef*fu"sion\, n. [L. effusio: cf. F. effusion.]
   1. The act of pouring out; as, effusion of water, of blood,
      of grace, of words, and the like.

            To save the effusion of my people's blood. --Dryden.

   2. That which is poured out, literally or figuratively.

            Wash me with that precious effusion, and I shall be
            whiter than sow.                      --Eikon
                                                  Basilike.

            The light effusions of a heedless boy. --Byron.

   3. (Pathol.)
      (a) 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.
      (b) The liquid escaping or exuded.

Source : WordNet®

effusion
     n 1: an unrestrained expression of emotion [syn: {gush}, {outburst},
           {blowup}, {ebullition}]
     2: flow under pressure