The Collaborative International Dictionary of English v.0.48:

Dedicate \Ded"i*cate\, v. t. [imp. & p. p. Dedicated; p. pr. &
   vb. n. Dedicating.]
   1. To set apart and consecrate, as to a divinity, or for
      sacred uses; to devote formally and solemnly; as, to
      dedicate vessels, treasures, a temple, or a church, to a
      religious use.
      [1913 Webster]

            Vessels of silver, and vessels of gold, . . . which
            also king David did dedicate unto the Lord. --2 Sam.
                                                  viii. 10, 11.
      [1913 Webster]

            We have come to dedicate a portion of that field as
            a final resting place for those who here gave their
            lives that that nation might live. . . . But in a
            larger sense we can not dedicate, we can not
            consecrate, we can not hallow this ground. --A.
                                                  Lincoln.
      [1913 Webster]

   2. To devote, set apart, or give up, as one's self, to a duty
      or service.
      [1913 Webster]

            The profession of a soldier, to which he had
            dedicated himself.                    --Clarendon.
      [1913 Webster]

   3. To inscribe or address, as to a patron.
      [1913 Webster]

            He complied ten elegant books, and dedicated them to
            the Lord Burghley.                    --Peacham.

   Syn: See Addict.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

dedicated \dedicated\ adj.
   1. wholly committed to a purpose or cause; as, a dedicated
      musician.

   Syn: devoted.
        [WordNet 1.5]

   2. zealous in loyalty or affection; as, dedicated nurses.

   Syn: devoted.
        [WordNet 1.5]

   3. set apart especially for a higher purpose; as, a life
      dedicated to science. [Narrower terms: consecrated (vs.
      desecrated), consecrate]

   Syn: dedicated to(predicate), devoted to(predicate).
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

dedicated
    adj 1: devoted to a cause or ideal or purpose; "a dedicated
           dancer"; "dedicated teachers"; "dedicated to the
           proposition that all men are created equal"- A.Lincoln
           [ant: undedicated]
    2: solemnly dedicated to or set apart for a high purpose; "a
       life consecrated to science"; "the consecrated chapel"; "a
       chapel dedicated to the dead of World War II" [syn:
       consecrated, consecrate, dedicated] [ant: desecrated]

Moby Thesaurus II by Grady Ward, 1.0:

91 Moby Thesaurus words for "dedicated":
   abandoned, afire, altruistic, ardent, beatified, blessed, bound,
   bound and determined, burning, canonized, committed, consecrated,
   constant, decided, decisive, definite, determined, devoted, devout,
   disinterested, earnest, faithful, fast, fervent, fervid, fiery,
   flaming, hallowed, hearty, heated, hot, hot-blooded, humble,
   impassioned, in earnest, intense, intent, intent on, loyal, modest,
   obstinate, on fire, passionate, perfervid, persevering, persistent,
   purposeful, red-hot, relentless, resolute, resolved, sacrificing,
   sainted, saintly, sanctified, self-abasing, self-abnegating,
   self-abnegatory, self-denying, self-devoted, self-effacing,
   self-forgetful, self-immolating, self-neglectful, self-neglecting,
   self-renouncing, self-sacrificing, self-unconscious, selfless,
   serious, set apart, sincere, single-minded, spirited, staunch,
   steadfast, tenacious, tested, tried, tried and true, true,
   unacquisitive, unpossessive, unpretentious, unselfish,
   unsparing of self, vehement, warm, white-hot, wholehearted,
   zealous