The Collaborative International Dictionary of English v.0.48:

Declaration \Dec`la*ra"tion\, n. [F. d['e]claration, fr. L.
   declaratio, fr. declarare. See Declare.]
   1. The act of declaring, or publicly announcing; explicit
      asserting; undisguised token of a ground or side taken on
      any subject; proclamation; exposition; as, the declaration
      of an opinion; a declaration of war, etc.
      [1913 Webster]

   2. That which is declared or proclaimed; announcement;
      distinct statement; formal expression; avowal.
      [1913 Webster]

            Declarations of mercy and love . . . in the Gospel.
                                                  --Tillotson.
      [1913 Webster]

   3. The document or instrument containing such statement or
      proclamation; as, the Declaration of Independence (now
      preserved in Washington).
      [1913 Webster]

            In 1776 the Americans laid before Europe that noble
            Declaration, which ought to be hung up in the
            nursery of every king, and blazoned on the porch of
            every royal palace.                   --Buckle.
      [1913 Webster]

   4. (Law) That part of the process or pleadings in which the
      plaintiff sets forth in order and at large his cause of
      complaint; the narration of the plaintiff's case
      containing the count, or counts. See Count, n., 3.
      [1913 Webster]

   Declaration of Independence. (Amer. Hist.) See Declaration
      of Independence in the vocabulary. See also under
      Independence.

   Declaration of rights. (Eng. Hist) See Bill of rights,
      under Bill.

   Declaration of trust (Law), a paper subscribed by a grantee
      of property, acknowledging that he holds it in trust for
      the purposes and upon the terms set forth. --Abbott.
      [1913 Webster]

WordNet (r) 3.0 (2006):

declaration
    n 1: a statement that is emphatic and explicit (spoken or
         written)
    2: (law) unsworn statement that can be admitted in evidence in a
       legal transaction; "his declaration of innocence"
    3: a statement of taxable goods or of dutiable properties
    4: (contract bridge) the highest bid becomes the contract
       setting the number of tricks that the bidder must make [syn:
       contract, declaration]
    5: a formal public statement; "the government made an
       announcement about changes in the drug war"; "a declaration
       of independence" [syn: announcement, proclamation,
       annunciation, declaration]
    6: a formal expression by a meeting; agreed to by a vote [syn:
       resolution, declaration, resolve]

Moby Thesaurus II by Grady Ward, 1.0:

131 Moby Thesaurus words for "declaration":
   Parthian shot, acceptance, acknowledgment, address, admission,
   advertisement, affidavit, affirmance, affirmation, allegation,
   allowance, announcement, annunciation, answer, apostrophe,
   appointment, appreciation, assertion, asseveration, attest,
   attestation, averment, avouchment, avowal, bill, bill of complaint,
   brevet, broadcast, bull, bulletin board, circular, claim, comment,
   communication, communique, complaint, compurgation, concession,
   conclusion, confession, confession of faith, crack, creed,
   declaration of faith, decree, decree-law, decreement, decretal,
   decretum, deposition, dictum, diktat, disclosure, edict, edictum,
   encyclical, enunciation, exclamation, expression, fiat, greeting,
   information, instrument in proof, interjection, ipse dixit, law,
   legal evidence, libel, manifesto, mention, narratio,
   nolle prosequi, nonsuit, note, notice, notification, observation,
   ordinance, ordonnance, phrase, position, position paper,
   positive declaration, predicate, predication, proclamation,
   profession, program, programma, promulgation, pronouncement,
   pronunciamento, proposition, protest, protestation, public notice,
   publication, question, recognition, reflection, remark, report,
   rescript, revelation, rule, ruling, say, say-so, saying,
   senatus consult, senatus consultum, sentence, stance, stand,
   statement, statement of facts, subjoinder, sworn evidence,
   sworn statement, sworn testimony, testimonial, testimonium,
   testimony, thought, ukase, utterance, vouch, white book,
   white paper, witness, word



Bouvier's Law Dictionary, Revised 6th Ed (1856):

DECLARATION, pleading. A declaration is a specification, in a methodical and
logical form, of the circumstances which constitute the plaintiff's cause of
action. 1 Chit. Pl. 248; Co. Litt. 17, a, 303, a; Bac. Abr. Pleas, B; Com.
Dig. Pleader, C 7; Lawes on Pl. 35; Steph Pl. 36; 6 Serg. & Rawle, 28. In
real actions, it is most properly called the count; in a personal one, the
declaration. Steph. Pl. 36 Doct. Pl. 83; Lawes, Plead. 33; see P. N. B. 16,
a, 60, d. The latter, however, is now the general term; being that commonly
used when referring to real and personal actions without distinction. 3
Bouv. Inst. n. 2815.
     2. The declaration in an action at law answers to the bill in chancery,
the libel of the civilians, and the allegation of the ecclesiastical courts.
     3. It may be considered with reference, 1st. To those general
requisites or qualities which govern the whole declaration; and 2d. To its
form, particular parts, and requisites.
     4.-1. The general requisites or qualities of a declaration are
first, that it correspond with the process. But, according to the present
practice of the courts, oyer of the writ cannot be craved; and a variance
between the writ and declaration cannot be pleaded in abatement. 1 Saund.
318; a.
     5.  Secondly. The second general requisite of a declaration is, that
it contain a statement of all the facts necessary in point of law, to
sustain the action, and no more. Co. Litt. 303, a; Plowd. 84, 122. See 2
Mass. 863; Cowp. 682; 6 East, R. 422 5 T. R. 623; Vin. Ab. Declarations.
     6.  Thirdly. These circumstances must be stated with certainty and
truth. The certainty necessary in a declaration is, to a certain intent in
general, which should pervade the whole declaration, and is particularly
required in setting forth, 1st. The parties; it must be stated with
certainty who are the parties to the suit, and therefore a declaration by or
against "C D and Company," not being a corporation, is insufficient. See
Com. Dig. Pleader, C I 8 1 Camp. R. 446 I T. R. 508; 3 Caines, R. 170. 2d.
The time; in personal actions the declaration must, in general, state a time
when every material or traversable fact happened; and when a venue is
necessary, time must also, be mentioned. 5 T. R. 620; Com. Dig. Plead. C 19;
Plowd. 24; 14 East, R. 390.; The precise time, however, is not material; 2
Dall. 346; 3 Johns. R. 43; 13 Johns. R. 253; unless it constitutes a
material part of the contract declared upon, or where the date, &c., of a
written contract or record, is averred; 4 T. R. 590 10 Mod. 313 2 Camp. R.
307, 8, n.; or, in ejectment, in which the demise must be stated to have
been made after the title of the lessor of the plaintiff, and his right of
entry, accrued. 2 East, R. 257; 1 Johns. Cas. 283. 3d. The Place. See Venue.
4th. Other circumstances necessary to maintain the action.
     7.-2. The parts and particular requisites of a declaration are,
first, the title of the court and term. See 1 Chit. Pl. 261, et seq.
     8.  Secondly. The venue. Immediately after the title of the
declaration follows the statement in the margin of the venue, or county in
which the facts are alleged to have occurred, and in which the cause is
tried. See Venue.
     9.  Thirdly. The commencement. What is termed the commencement of the
declaration follows the venue in the margin, and precedes the more
circumstantial statement of the cause of action. It contains a statement,
1st. Of the names of the parties to the suit, and if they sue or be sued in
another right, or in a political capacity, (as executors, assignees, qui
lam, &c.) of the character or right in respect of which they are parties to
the suit. 2d. Of the mode in  which the defendant has been brought into
court; and, 3d. A brief recital of the form of action to be proceeded in. 1
Saund. 318, Id. 111, 112; 6 T. R. 130.
    10.  Fourthly. The statement of the cause (if action, in which all the
requisites of certainty before mentioned must be observed, necessarily
varies, according to the circumstances of each particular case, and the form
of action, whether in assumpsit, debt, covenant, detinue, case, trover,
replevin or trespass.
    11.  Fifthly. The several counts. A declaration may consist of as many
counts as the case requires, and the jury may assess entire or distinct
damages on. all the counts; 3 Wils. R. 185; 2 Bay, R. 206; and it is usual,
particularly in actions of assumpsit, debt on simple contract, and actions
on the case, to set forth the plaintiff's cause of action in various shapes
in different counts, so that if the plaintiff fail in proof of one count, he
may succeed in another. 3 Bl. Com. 295.
    12.  Sixthly. The conclusion. In personal and mixed actions the
declaration should conclude to the damage of the plaintiff; Com. Dig.
Pleader, C 84; 10 Co. 116, b. 117, a.; unless in scire facias and in penal
actions at the suit of a common informer.
    13.  Seventhly. The profert and pledges. In an action at the suit of an
executor or administrator, immediately after the conclusion to the damages,
&c., and before the pledges, a profert of the letters testamentary or
letters of administration should be made. Bac. Abr. Executor, C; Dougl. 6,
in notes. At the end of the declaration, it is usual to add the plaintiff is
common pledges to prosecute, John Doe and Richard Roe.
    14. A declaration may be general or special; for example, in debt or
bond, a declaration counting on the penal part only, is general; when it
sets out both the penalty and the condition, and assigns the breach, it is
special. Gould on Pl. c. 4, Sec. 50. See, generally, Bouv. Inst. Index, h.t.
1 Chit. Pl. 248 to 402; Lawes, Pl. Index) h.t.; Arch. Civ. Pl. index, h.t.;
Steph. Pl. h.t.; Grab. Pr. h.t.; Com. Dig. Pleader, h.t.; Dane's Ab. h.t.;
United States Dig. Pleadings ii.