The Collaborative International Dictionary of English v.0.48:

Subjective \Sub*jec"tive\, a. [L. subjectivus: cf. F.
   subjectif.]
   1. Of or pertaining to a subject.
      [1913 Webster]

   2. Especially, pertaining to, or derived from, one's own
      consciousness, in distinction from external observation;
      ralating to the mind, or intellectual world, in
      distinction from the outward or material excessively
      occupied with, or brooding over, one's own internal
      states.
      [1913 Webster]

   Note: In the philosophy of the mind, subjective denotes what
         is to be referred to the thinking subject, the ego;
         objective, what belongs to the object of thought, the
         non-ego. See Objective, a., 2. --Sir W. Hamilton.
         [1913 Webster]

   3. (Lit. & Art) Modified by, or making prominent, the
      individuality of a writer or an artist; as, a subjective
      drama or painting; a subjective writer.
      [1913 Webster]

   Syn: See Objective.
        [1913 Webster]

   Subjective sensation (Physiol.), one of the sensations
      occurring when stimuli due to internal causes excite the
      nervous apparatus of the sense organs, as when a person
      imagines he sees figures which have no objective reality.
      [1913 Webster] -- Sub*jec"tive*ly, adv. --
      Sub*jec"tive*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

subjective
    adj 1: taking place within the mind and modified by individual
           bias; "a subjective judgment" [ant: nonsubjective,
           objective]
    2: of a mental act performed entirely within the mind; "a
       cognition is an immanent act of mind" [syn: immanent,
       subjective] [ant: transeunt, transient]

Moby Thesaurus II by Grady Ward, 1.0:

55 Moby Thesaurus words for "subjective":
   abstract, biased, cerebral, conceptive, conceptual, deep-seated,
   egocentric, egoistic, endopsychic, esoteric, idiosyncratic,
   immanent, implanted, implicit, inalienable, individual, indwelling,
   infixed, ingoing, ingrained, inherent, inner, inner-directed,
   intellectual, intelligent, internal, intrinsic, introversive,
   introvert, introverted, inward, inwrought, irreducible, mental,
   noetic, nominative, nonobjective, noological, personal, phrenic,
   prejudiced, private, psychic, psychologic, rational, reasoning,
   resident, secret, self-serving, selfish, spiritual, thinking,
   unalienable, unchallengeable, unquestionable