The Collaborative International Dictionary of English v.0.48:

Cognition \Cog*ni"tion\, n. [L. cognitio, fr. cognoscere,
   cognitum, to become acquainted with, to know; co- + noscere,
   gnoscere, to get a knowledge of. See Know, v. t.]
   1. The act of knowing; knowledge; perception.
      [1913 Webster]

            I will not be myself nor have cognation
            Of what I feel: I am all patience.    --Shak.
      [1913 Webster]

   2. That which is known.
      [1913 Webster]

WordNet (r) 3.0 (2006):

cognition
    n 1: the psychological result of perception and learning and
         reasoning [syn: cognition, knowledge, noesis]