The Collaborative International Dictionary of English v.0.48:

Exudation \Ex`u*da"tion\, n.
   The act of exuding; sweating; a discharge of humors,
   moisture, juice, or gum, as through pores or incisions; also,
   the substance exuded.
   [1913 Webster]

         Resins, a class of proximate principles, existing in
         almost all plants and appearing on the external surface
         of many of them in the form of exudations. --Am. Cyc.
   [1913 Webster]

WordNet (r) 3.0 (2006):

exudation
    n 1: a substance that oozes out from plant pores [syn:
         exudate, exudation]
    2: the process of exuding; the slow escape of liquids from blood
       vessels through pores or breaks in the cell membranes [syn:
       exudation, transudation]