The Collaborative International Dictionary of English v.0.48:

Explicit \Ex"pli*cit\ [LL., an abbreviation of explicitus (est
   liber) the book (which anciently was a roll of parchment) is
   unfolded (and, of course, "finished"). See Explicit, a.]
   A word formerly used (as finis is now) at the conclusion of a
   book to indicate the end.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Explicit \Ex*plic"it\, a. [L. explicitus; p. p. of explicare to
   unfold: cf. F. explicite. See Explicate, Exploit.]
   1. Not implied merely, or conveyed by implication; distinctly
      stated; plain in language; open to the understanding;
      clear; not obscure or ambiguous; express; unequivocal; as,
      an explicit declaration. Opposite of implicit.
      [1913 Webster]

            The language of the charter was too explicit to
            admit of a doubt.                     --Bancroft.
      [1913 Webster]

   2. Having no disguised meaning or reservation; unreserved;
      outspoken; -- applied to persons; as, he was earnest and
      explicit in his statement.
      [1913 Webster]

   Explicit function. (Math.) See under Function.

   Syn: Express; clear; plain; open; unreserved; unambiguous.

   Usage: Explicit, Express. Explicit denotes a setting
          forth in the plainest language, so that the meaning
          can not be misunderstood; as, an explicit promise.
          Express is stronger than explicit: it adds force to
          clearness. An express promise or engagement is not
          only unambiguous, but stands out in bold relief, with
          the most binding hold on the conscience. An explicit
          statement; a clear and explicit notion; explicit
          direction; no words can be more explicit. An explicit
          command; an express prohibition. "An express
          declaration goes forcibly and directly to the point.
          An explicit declaration leaves nothing ambiguous."
          --C. J. Smith.
          [1913 Webster]

WordNet (r) 3.0 (2006):

explicit
    adj 1: precisely and clearly expressed or readily observable;
           leaving nothing to implication; "explicit instructions";
           "she made her wishes explicit"; "explicit sexual scenes"
           [syn: explicit, expressed] [ant: implicit,
           inexplicit]
    2: in accordance with fact or the primary meaning of a term
       [syn: denotative, explicit]

Moby Thesaurus II by Grady Ward, 1.0:

139 Moby Thesaurus words for "explicit":
   absolute, accurate, admitting no exception, all-out, apparent,
   artless, bluff, blunt, broad, brusque, candid, categorical,
   categorically, certain, clean-cut, clear, clear as crystal,
   clear as day, clear-cut, coherent, complete, conclusive, connected,
   consistent, correct, crisp, crystal-clear, crystalline, decided,
   decisive, defined, definite, definitely, definitive, determinate,
   direct, discernible, distinct, downright, entire, evident, exact,
   explicitly, express, final, fixed, flat, flat-out, forthright,
   frank, frankhearted, free, free-speaking, free-spoken,
   free-tongued, genuine, global, heart-to-heart, implicit,
   inappealable, indisputable, indubitable, ingenuous, limpid,
   loud and clear, lucid, luminous, manifest, noticeable, observable,
   obvious, open, open-and-shut, openhearted, out-and-out, outright,
   outspoken, palpable, patent, pellucid, perceivable, perceptible,
   peremptory, perfect, perspicuous, plain, plain as day,
   plain-spoken, positive, precise, round, seeable, self-evident,
   self-explaining, self-explanatory, simple, sincere, specific,
   specifically, stated, straight, straight-out, straightforward,
   sure, tangible, to be seen, total, translucent, transparent,
   transpicuous, unambiguous, unchecked, uncircumscribed,
   unconditional, unconditioned, unconfused, unconstrained,
   understandable, undoubting, unequivocal, unguarded, unhampered,
   unhesitating, univocal, unlimited, unmistakable, unmitigated,
   unqualified, unquestioning, unreserved, unrestrained, unrestricted,
   unwaivable, utter, visible, well-defined, whole, without exception,
   without reserve