Source : Webster's Revised Unabridged Dictionary (1913)

Liable \Li"a*ble\ (l[imac]"[.a]*b'l), a. [From F. lier to bind,
   L. ligare. Cf. {Ally}, v. t., {Ligature}.]
   1. Bound or obliged in law or equity; responsible;
      answerable; as, the surety is liable for the debt of his
      principal.

   2. Exposed to a certain contingency or casualty, more or less
      probable; -- with to and an infinitive or noun; as, liable
      to slip; liable to accident.

   Syn: Accountable; responsible; answerable; bound; subject;
        obnoxious; exposed.

   Usage: {Liable}, {Subject}. Liable refers to a future
          possible or probable happening which may not actually
          occur; as, horses are liable to slip; even the
          sagacious are liable to make mistakes. Subject refers
          to any actual state or condition belonging to the
          nature or circumstances of the person or thing spoken
          of, or to that which often befalls one. One whose
          father was subject to attacks of the gout is himself
          liable to have that disease. Men are constantly
          subject to the law, but liable to suffer by its
          infraction.

                Proudly secure, yet liable to fall. --Milton.

                All human things are subject to decay. --Dryden.

Source : WordNet®

liable
     adj 1: at risk of or subject to experiencing something usually
            unpleasant; "he is apt to lose"; "she is liable to
            forget" [syn: {apt(p)}, {liable(p)}]
     2: subject to legal action; "liable to criminal charges" [syn:
        {liable(p)}]
     3: (often followed by `to') likely to be affected with; "liable
        to diabetes" [syn: {liable(p)}, {nonimmune}, {nonresistant},
         {unresistant}]
     4: held legally responsible; "men between the ages of 18 and 35
        were liable for military service"