The Collaborative International Dictionary of English v.0.48:

Qualify \Qual"i*fy\, v. t. [imp. & p. p. Qualified; p. pr. &
   vb. n. Qualifying.] [F. qualifier, LL. qualificare, fr. L.
   qualis how constituted, as + -ficare (in comp.) to make. See
   Quality, and -Fy.]
   1. To make such as is required; to give added or requisite
      qualities to; to fit, as for a place, office, occupation,
      or character; to furnish with the knowledge, skill, or
      other accomplishment necessary for a purpose; to make
      capable, as of an employment or privilege; to supply with
      legal power or capacity.
      [1913 Webster]

            He had qualified himself for municipal office by
            taking the oaths to the sovereigns in possession.
                                                  --Macaulay.
      [1913 Webster]

   2. To give individual quality to; to modulate; to vary; to
      regulate.
      [1913 Webster]

            It hath no larynx . . . to qualify the sound. --Sir
                                                  T. Browne.
      [1913 Webster]

   3. To reduce from a general, undefined, or comprehensive
      form, to particular or restricted form; to modify; to
      limit; to restrict; to restrain; as, to qualify a
      statement, claim, or proposition.
      [1913 Webster]

   4. Hence, to soften; to abate; to diminish; to assuage; to
      reduce the strength of, as liquors.
      [1913 Webster]

            I do not seek to quench your love's hot fire,
            But qualify the fire's extreme rage.  --Shak.
      [1913 Webster]

   5. To soothe; to cure; -- said of persons. [Obs.]
      [1913 Webster]

            In short space he has them qualified. --Spenser.
      [1913 Webster]

   Syn: To fit; equip; prepare; adapt; capacitate; enable;
        modify; soften; restrict; restrain; temper.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Qualify \Qual"i*fy\, v. i.
   1. To be or become qualified; to be fit, as for an office or
      employment.
      [1913 Webster]

   2. To obtain legal power or capacity by taking the oath, or
      complying with the forms required, on assuming an office.
      [1913 Webster]

WordNet (r) 3.0 (2006):

qualify
    v 1: prove capable or fit; meet requirements [syn: qualify,
         measure up]
    2: pronounce fit or able; "She was qualified to run the
       marathon"; "They nurses were qualified to administer the
       injections" [ant: disqualify]
    3: make more specific; "qualify these remarks" [syn: qualify,
       restrict]
    4: make fit or prepared; "Your education qualifies you for this
       job" [syn: qualify, dispose] [ant: disqualify,
       indispose, unfit]
    5: specify as a condition or requirement in a contract or
       agreement; make an express demand or provision in an
       agreement; "The will stipulates that she can live in the
       house for the rest of her life"; "The contract stipulates the
       dates of the payments" [syn: stipulate, qualify,
       condition, specify]
    6: describe or portray the character or the qualities or
       peculiarities of; "You can characterize his behavior as that
       of an egotist"; "This poem can be characterized as a lament
       for a dead lover" [syn: qualify, characterize,
       characterise]
    7: add a modifier to a constituent [syn: modify, qualify]

Moby Thesaurus II by Grady Ward, 1.0:

173 Moby Thesaurus words for "qualify":
   abate, accommodate, adapt, adjust, adjust to, alter, ameliorate,
   answer, ascribe, assign, assuage, attribute, attune, authorize,
   avail, be OK, be blooded, be equal to, be successful, bear, better,
   bound, box, box in, box up, break up, capacitate, catch on,
   certify, change, check out, circumscribe, click, come off,
   condition, confine, connect, contain, convert, copyright, cramp,
   deform, denature, diminish, discipline, distinguish, diversify, do,
   do it, do the job, draw the line, enable, equip, farewell,
   fill the bill, fit, fit out, fulfill, furnish, get by, go,
   go around, go great guns, go off, go over, go over big, go to town,
   graduate, hack it, have the qualifications, hedge, hedge about,
   hem, hem in, hold, improve, impute, individualize, individuate,
   just do, keep from spreading, keep within bounds, leaven, limit,
   localize, make a hit, make reservations, make the grade, mark,
   measure up, meet, meet requirements, meet with success, meliorate,
   mitigate, moderate, modify, modulate, mutate, narrow, overthrow,
   palliate, pass, pass muster, patent, predicate, prepare, prevail,
   prosper, put in trim, put in tune, re-create, reach, ready,
   realign, rebuild, reconstruct, redesign, reduce, refit, reform,
   register, regulate by, relate, remake, renew, reshape, restrain,
   restrict, restructure, revamp, revive, ring the changes, satisfy,
   scant, season, serve, serve the purpose, set conditions,
   set limits, set terms, shift the scene, shuffle the cards,
   signalize, soften, specialize, specifically provide, stand,
   stand up, stint, stipulate, stipulate for, straiten, stretch,
   subvert, succeed, suffice, suit, take, take it, temper, tighten,
   tune, turn the scale, turn the tables, turn the tide,
   turn upside down, vary, work, work a change, work well,
   work wonders, worsen