The Collaborative International Dictionary of English v.0.48:

Balance \Bal"ance\ (b[a^]l"ans), v. t. [imp. & p. p. Balanced
   (b[a^]l"anst); p. pr. & vb. n. Balancing
   (b[a^]l"an*s[i^]ng).] [From Balance, n.: cf. F. balancer.]
   1. To bring to an equipoise, as the scales of a balance by
      adjusting the weights; to weigh in a balance.
      [1913 Webster]

   2. To support on a narrow base, so as to keep from falling;
      as, to balance a plate on the end of a cane; to balance
      one's self on a tight rope.
      [1913 Webster]

   3. To equal in number, weight, force, or proportion; to
      counterpoise, counterbalance, counteract, or neutralize.
      [1913 Webster]

            One expression . . . must check and balance another.
                                                  --Kent.
      [1913 Webster]

   4. To compare in relative force, importance, value, etc.; to
      estimate.
      [1913 Webster]

            Balance the good and evil of things.  --L'Estrange.
      [1913 Webster]

   5. To settle and adjust, as an account; to make two accounts
      equal by paying the difference between them.
      [1913 Webster]

            I am very well satisfied that it is not in my power
            to balance accounts with my Maker.    --Addison.
      [1913 Webster]

   6. To make the sums of the debits and credits of an account
      equal; -- said of an item; as, this payment, or credit,
      balances the account.
      [1913 Webster]

   7. To arrange accounts in such a way that the sum total of
      the debits is equal to the sum total of the credits; as,
      to balance a set of books.
      [1913 Webster]

   8. (Dancing) To move toward, and then back from,
      reciprocally; as, to balance partners.
      [1913 Webster]

   9. (Naut.) To contract, as a sail, into a narrower compass;
      as, to balance the boom mainsail.
      [1913 Webster]

   Balanced valve. See Balance valve, under Balance, n.
      [1913 Webster]

   Syn: To poise; weigh; adjust; counteract; neutralize;
        equalize.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

balanced \bal"anced\ adj.
   being in a state of proper balance or equilibrium; --
   opposite of unbalanced. the carefully balanced seesaw a
   properly balanced symphony orchestra a balanced assessment of
   intellectual and cultural history a balanced blend of
   whiskeys the educated man shows a balanced development of all
   his powers [Narrower terms: counterbalanced,
   counter-balanced, counterpoised; well-balanced; poised]
   [Related terms: stable --- (maintaining equilibrium)]
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

balanced
    adj 1: being in a state of proper equilibrium; "the carefully
           balanced seesaw"; "a properly balanced symphony
           orchestra"; "a balanced assessment of intellectual and
           cultural history"; "a balanced blend of whiskeys"; "the
           educated man shows a balanced development of all his
           powers" [ant: imbalanced, unbalanced]

Moby Thesaurus II by Grady Ward, 1.0:

149 Moby Thesaurus words for "balanced":
   accordant, alike, all there, apoise, assured, automatic,
   clearheaded, clearminded, coequal, collected, commonsense,
   compos mentis, composed, concinnate, concinnous, confident,
   consistent, consonant, constant, continuous, cool, coolheaded,
   coordinate, correspondent, defensible, deserved, due, equable,
   equal, equanimous, equibalanced, equilateral, equilibrious,
   equiponderant, equiponderous, equitable, euphonic, euphonical,
   euphonious, eurythmic, even, evenhanded, fair, fair and square,
   fast, fiducial, finished, firm, firm as Gibraltar, fit, flat,
   flowing, fluent, good, harmonious, healthy-minded, homogeneous,
   immutable, imperturbable, in equilibrium, invariable, just,
   justifiable, justified, lawful, legal, level, levelheaded, logical,
   lucid, measured, mechanical, meet, meet and right, mentally sound,
   merited, methodic, monolithic, normal, of a piece, of sound mind,
   ordered, orderly, persistent, philosophical, poised, practical,
   pragmatic, predictable, proper, proportioned, rational, reasonable,
   recollected, regular, reliable, right, right and proper, rightful,
   robotlike, sane, sane-minded, secure, self-assured, self-confident,
   self-controlled, self-possessed, self-restrained, sensible, smooth,
   smooth-sounding, sober, sober-minded, solid, sound, sound-minded,
   square, stable, steadfast, steady, substantial, sweet, symmetric,
   symmetrical, systematic, together, tripping, unbroken,
   unchangeable, unchanged, unchanging, undeviating, undifferentiated,
   undiversified, unflappable, unflinching, uniform, unruffled,
   unshakable, unvaried, unvarying, unwavering, warrantable,
   warranted, well-balanced, well-set, well-set-up, wholesome,
   without nerves