The Collaborative International Dictionary of English v.0.48:

Confine \Con*fine"\ (k[o^]n*f[imac]n"), v. t. [imp. & p. p.
   Confined; p. pr. & vb. n. Confining.] [F. confiner to
   border upon, LL. confinare to set bounds to; con- + finis
   boundary, end. See Final, Finish.]
   To restrain within limits; to restrict; to limit; to bound;
   to shut up; to inclose; to keep close.
   [1913 Webster]

         Now let not nature's hand
         Keep the wild flood confined! let order die! --Shak.
   [1913 Webster]

         He is to confine himself to the compass of numbers and
         the slavery of rhyme.                    --Dryden.
   [1913 Webster]

   To be confined, to be in childbed.

   Syn: To bound; limit; restrain; imprison; immure; inclose;
        circumscribe; restrict.
        [1913 Webster]

WordNet (r) 3.0 (2006):

confining
    adj 1: restricting the scope or freedom of action [syn:
           confining, constraining, constrictive, limiting,
           restricting]
    2: crowded; "close quarters" [syn: close, confining]