The Collaborative International Dictionary of English v.0.48:

Liege \Liege\ (l[=e]j), a. [OE. lige, lege, F. lige, LL. ligius,
   legius, liege, unlimited, complete, prob. of German origin;
   cf. G. ledig free from bonds and obstacles, MHG. ledec,
   ledic, lidic, freed, loosed, and Charta Ottonis de Benthem,
   ann. 1253, "ligius homo quod Teutonic[`e] dicitur ledigman,"
   i. e., uni soli homagio obligatus, free from all obligations
   to others; influenced by L. ligare to bind. G. ledig perh.
   orig. meant, free to go where one pleases, and is perh. akin
   to E. lead to conduct. Cf. Lead to guide.]
   1. Sovereign; independent; having authority or right to
      allegiance; as, a liege lord. --Chaucer.
      [1913 Webster]

            She looked as grand as doomsday and as grave;
            And he, he reverenced his liege lady there.
                                                  --Tennyson.
      [1913 Webster]

   2. serving an independent sovereign or master; bound by a
      feudal tenure; obliged to be faithful and loyal to a
      superior, as a vassal to his lord; faithful; loyal; as, a
      liege man; a liege subject.
      [1913 Webster]

   3. (Old Law) Full; perfect; complete; pure. --Burrill.
      [1913 Webster]

   Liege homage (Feudal Custom), that homage of one sovereign
      or prince to another which acknowledged an obligation of
      fealty and services.

   Liege poustie [L. legitima potestas] (Scots Law), perfect,
      i. e., legal, power; specif., having health requisite to
      do legal acts.

   Liege widowhood, perfect, i. e., pure, widowhood. [Obs.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Liege \Liege\ (l[=e]j), n.
   1. A free and independent person; specif., a lord paramount;
      a sovereign. --Mrs. Browning.
      [1913 Webster]

            The anointed sovereign of sighs and groans,
            Liege of all loiterers and malcontents. --Shak.
      [1913 Webster]

   2. The subject of a sovereign or lord; a liegeman.
      [1913 Webster]

            A liege lord seems to have been a lord of a free
            band; and his lieges, though serving under him, were
            privileged men, free from all other obligations,
            their name being due to their freedom, not to their
            service.                              --Skeat.
      [1913 Webster]

WordNet (r) 3.0 (2006):

liege
    adj 1: owing or owed feudal allegiance and service; "one's liege
           lord"; "a liege subject"
    n 1: a person holding a fief; a person who owes allegiance and
         service to a feudal lord [syn: vassal, liege,
         liegeman, liege subject, feudatory]
    2: a feudal lord entitled to allegiance and service [syn:
       liege, liege lord]
    3: city in eastern Belgium; largest French-speaking city in
       Belgium [syn: Liege, Luik]

Moby Thesaurus II by Grady Ward, 1.0:

81 Moby Thesaurus words for "liege":
   ardent, bondmaid, bondman, bondslave, bondsman, bondswoman, boss,
   bwana, captive, chattel, chattel slave, chef, chief,
   church dignitary, churl, client, concubine, constant, creature,
   debt slave, dependent, ecclesiarch, elder, employer, feudal,
   feudatory, flunky, follower, galley slave, goodman, guru,
   hanger-on, helot, homager, husband, inferior, lackey, liege lord,
   liege man, liege subject, lord, lord paramount, loyal, master,
   minion, myrmidon, odalisque, overlord, padrone, paramount,
   paterfamilias, patriarch, patron, peon, rabbi, resolute, retainer,
   sahib, seigneur, seignior, serf, servant, servile, slave, starets,
   staunch, steadfast, stooge, subject, subordinate, subservient,
   teacher, theow, thrall, tributary, true, underling, understrapper,
   vassal, villein, yeoman



Bouvier's Law Dictionary, Revised 6th Ed (1856):

LIEGE, from the Latin, ligare, to bind. The bond subsisting between the
subject and chief, or lord and vassal, binding the one to protection and
just government, the other to tribute and due subjection. The prince or
chief is called liege lord; the subjects liege men. The word is now applied
as if the liegance or bond were only to attach the people to the prince.
Stat. 8 Hen. VI. c. 10; 14 Hen. VIII. c. 2; 1 Bl. Com. 367.