The Collaborative International Dictionary of English v.0.48:

Subjection \Sub*jec"tion\, n. [L. subjectio: cf. OF. subjection,
   F. subj['e]tion. See Subject, a.]
   1. The act of subjecting, or of bringing under the dominion
      of another; the act of subduing.
      [1913 Webster]

            The conquest of the kingdom, and subjection of the
            rebels.                               --Sir M. Hale.
      [1913 Webster]

   2. The state of being subject, or under the power, control,
      and government of another; a state of obedience or
      submissiveness; as, the safety of life, liberty, and
      property depends on our subjection to the laws. "To be
      bound under subjection." --Chaucer.
      [1913 Webster]

            Likewise, ye wives, be in subjection to your own
            husbands.                             --1 Peter iii.
                                                  1.
      [1913 Webster]

            Because the subjection of the body to the will is by
            natural necessity, the subjection of the will unto
            God voluntary, we stand in need of direction after
            what sort our wills and desires may be rightly
            conformed to His.                     --Hooker.
      [1913 Webster]

WordNet (r) 3.0 (2006):

subjection
    n 1: forced submission to control by others [syn: subjugation,
         subjection]
    2: the act of conquering [syn: conquest, conquering,
       subjection, subjugation]

Moby Thesaurus II by Grady Ward, 1.0:

43 Moby Thesaurus words for "subjection":
   acceptance, acquiescence, assent, back seat, complaisance,
   compliance, conquest, consent, deference, domination, enslavement,
   homage, humbleness, humbling, humiliation, humility, inferiority,
   juniority, kneeling, lowliness, minority, nonopposal,
   nonopposition, nonresistance, obedience, obeisance, passiveness,
   passivity, resignation, resignedness, second fiddle, second string,
   secondariness, servility, subjugation, submission, submittal,
   subordinacy, subordination, subservience, supineness, third string,
   yielding



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

SUBJECTION. The obligation of one or more persons to act at the discretion,
or according to the judgment and will of others.
     2. Subjection is either private or public. By the former is meant the
subjection to the authority of private persons; as, of children to their
parents, of apprentices to their masters, and the like. By the latter is
understood the subjection to the authority of public persons. Rutherf. Inst.
B. 2, c. 8.