The Collaborative International Dictionary of English v.0.48:

Livable \Liv"a*ble\, a.
   1. Such as can be lived.
      [1913 Webster]

   2. Such as is pleasant to live in; fit or suitable to live
      in. [Colloq.]
      [1913 Webster]

            A more delightful or livable region is not easily to
            be found.                             --T. Arnold.
      [1913 Webster]

WordNet (r) 3.0 (2006):

livable
    adj 1: fit or suitable to live in or with; "livable conditions"
           [syn: livable, liveable] [ant: unlivable,
           unliveable]