The Collaborative International Dictionary of English v.0.48:

Pore \Pore\, n. [F., fr. L. porus, Gr. ? a passage, a pore. See
   Fare, v.]
   1. One of the minute orifices in an animal or vegetable
      membrane, for transpiration, absorption, etc.
      [1913 Webster]

   2. A minute opening or passageway; an interstice between the
      constituent particles or molecules of a body; as, the
      pores of stones.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pore \Pore\, v. i. [imp. & p. p. Pored; p. pr. & vb. n.
   Poring.] [OE. poren, of uncertain origin; cf. D. porren to
   poke, thrust, Gael. purr.]
   To look or gaze steadily in reading or studying; to fix the
   attention; to be absorbed; -- often with on or upon, and now
   usually with over."Painfully to pore upon a book." --Shak.
   [1913 Webster]

         The eye grows weary with poring perpetually on the same
         thing.                                   --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pore
    n 1: any tiny hole admitting passage of a liquid (fluid or gas)
    2: any small opening in the skin or outer surface of an animal
    3: a minute epidermal pore in a leaf or stem through which gases
       and water vapor can pass [syn: stoma, stomate, pore]
    v 1: direct one's attention on something; "Please focus on your
         studies and not on your hobbies" [syn: concentrate,
         focus, center, centre, pore, rivet]