The Collaborative International Dictionary of English v.0.48:

Intolerable \In*tol"er*a*ble\, a. [F. intol['e]rable, L.
   intolerabilis. See In- not, and Tolerable.]
   [1913 Webster]
   1. Not tolerable; not capable of being borne or endured; not
      proper or right to be allowed; insufferable;
      insupportable; unbearable; as, intolerable pain;
      intolerable heat or cold; an intolerable burden.
      [1913 Webster]

            His insolence is more intolerable
            Than all the princes in the land beside. --Shak.
      [1913 Webster]

   4. Enormous.
      [1913 Webster]

            This intolerable deal of sack.        --Shak.
      -- In*tol"er*a*ble*ness, n. -- In*tol"er*a*bly, adv.
      [1913 Webster]

WordNet (r) 3.0 (2006):

intolerable
    adj 1: incapable of being put up with; "an intolerable degree of
           sentimentality" [syn: intolerable, unbearable,
           unendurable] [ant: tolerable]