The Collaborative International Dictionary of English v.0.48:

Comprehension \Com`pre*hen"sion\, n. [L. comprehensio: cf. F.
   compr['e]hension.]
   1. The act of comprehending, containing, or comprising;
      inclusion.
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            In the Old Testament there is a close comprehension
            of the New; in the New, an open discovery of the
            Old.                                  --Hooker.
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   2. That which is comprehended or inclosed within narrow
      limits; a summary; an epitome. [Obs.]
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            Though not a catalogue of fundamentals, yet . . . a
            comprehension of them.                --Chillingworth.
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   3. The capacity of the mind to perceive and understand; the
      power, act, or process of grasping with the intellect;
      perception; understanding; as, a comprehension of abstract
      principles.
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   4. (Logic) The complement of attributes which make up the
      notion signified by a general term.
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   5. (Rhet.) A figure by which the name of a whole is put for a
      part, or that of a part for a whole, or a definite number
      for an indefinite.
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WordNet (r) 3.0 (2006):

comprehension
    n 1: an ability to understand the meaning or importance of
         something (or the knowledge acquired as a result); "how you
         can do that is beyond my comprehension"; "he was famous for
         his comprehension of American literature" [ant:
         incomprehension]
    2: the relation of comprising something; "he admired the
       inclusion of so many ideas in such a short work" [syn:
       inclusion, comprehension]