The Collaborative International Dictionary of English v.0.48:

Intention \In*ten"tion\, n. [F. intention, L. intentio. See
   Intend, and cf. Intension.]
   [1913 Webster]
   1. A stretching or bending of the mind toward an object;
      closeness of application; fixedness of attention;
      earnestness.
      [1913 Webster]

            Intention is when the mind, with great earnestness,
            and of choice, fixes its view on any idea. --Locke.
      [1913 Webster]

   2. A determination to act in a certain way or to do a certain
      thing; purpose; design; as, an intention to go to New
      York.
      [1913 Webster]

            Hell is paved with good intentions.   --Johnson.
      [1913 Webster]

   3. The object toward which the thoughts are directed; end;
      aim.
      [1913 Webster]

            In [chronical distempers], the principal intention
            is to restore the tone of the solid parts.
                                                  --Arbuthnot.
      [1913 Webster]

   4. The state of being strained. See Intension. [Obs.]
      [1913 Webster]

   5. (Logic) Any mental apprehension of an object.
      [1913 Webster]

   First intention (Logic), a conception of a thing formed by
      the first or direct application of the mind to the
      individual object; an idea or image; as, man, stone.

   Second intention (Logic), a conception generalized from
      first intuition or apprehension already formed by the
      mind; an abstract notion; especially, a classified notion,
      as species, genus, whiteness.

   To heal by the first intention (Surg.), to cicatrize, as a
      wound, without suppuration.

   To heal by the second intention (Surg.), to unite after
      suppuration.

   Syn: Design; purpose; object; aim; intent; drift; purport;
        meaning. See Design.
        [1913 Webster]

WordNet (r) 3.0 (2006):

intention
    n 1: an anticipated outcome that is intended or that guides your
         planned actions; "his intent was to provide a new
         translation"; "good intentions are not enough"; "it was
         created with the conscious aim of answering immediate
         needs"; "he made no secret of his designs" [syn: purpose,
         intent, intention, aim, design]
    2: (usually plural) the goal with respect to a marriage
       proposal; "his intentions are entirely honorable"
    3: an act of intending; a volition that you intend to carry out;
       "my intention changed once I saw her"

Moby Thesaurus II by Grady Ward, 1.0:

119 Moby Thesaurus words for "intention":
   aim, ambition, animus, appetence, appetency, appetite, approach,
   arrangement, aspiration, attack, basis, blueprint, blueprinting,
   calculation, calling, cause, charting, choice, command, conation,
   conatus, conception, consideration, contrivance, decision, design,
   desire, determination, device, discretion, disposition, end,
   enterprise, envisagement, fancy, figuring, foresight, forethought,
   free choice, free will, game, goal, graphing, ground, ground plan,
   guidelines, guiding light, guiding star, hope, idea, ideal,
   inclination, inspiration, intendment, intent, layout, liking,
   lineup, lodestar, long-range plan, lust, mainspring, mapping,
   master plan, matter, meaning, method, methodology, mind, motive,
   object, objective, operations research, organization, passion,
   plan, planning, planning function, pleasure, prearrangement,
   principle, procedure, program, program of action, project, purpose,
   rationalization, reason, resolution, sake, schedule, schema,
   schematism, schematization, scheme, scheme of arrangement, score,
   setup, sexual desire, source, spring, strategic plan, strategy,
   system, systematization, tactical plan, tactics, target,
   the big picture, the picture, ulterior motive, velleity, vocation,
   volition, way, will, will power, wish, working plan



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

INTENTION. A design, resolve, or determination of the mind.
     2. Intention is required in the commission of crimes and injuries, in
making contracts, and wills.
     3.-1. Every crime must have necessarily two constituent parts,
namely, an act forbidden by law, and an intention. The act is innocent or
guilty just as there was or was not an intention to commit a crime; for
example, a man embarks on board of a ship, at New York, for the purpose of
going to New Orleans; if he went with an intention to perform a lawful act,
he is perfectly innocent; but if his intention was to levy war against the
United States, he is guilty of an overt act of treason. Cro. Car. 332; Fost.
202, 203; Hale, P. C. 116. The same rule prevails in numerous civil cases;
in actions founded on malicious injuries, for instance, it is necessary to
prove that the act was accompanied, by a wrongful and malicious intention. 2
Stark. Ev. 739.
     4. The intention is to be proved, or it is inferred by the law. The
existence of the intention is usually matter of inference; and proof of
external and visible acts and conduct serves to indicate, more or less
forcibly, the particular intention. But, in some cases, the inference of
intention necessarily arises from the facts. Exteriora acta indicant
interiora animi secreta. 8 Co. 146. It is a universal rule, that a man shall
be taken to intend that which he does, or which is the necessary and
immediate consequence of his act; 3 M. & S. 15; Hale, P. C. 229; in cases of
homicide, therefore, malice will generally be inferred by the law. Vide
Malice' and Jacob's Intr. to the Civ. Law, Reg. 70; Dig. 24, 18.
     5. But a bare intention to commit a crime, without any overt act
towards its commission, although punishable in foro, conscientiae, is not a
crime or offence for which the party can be indicted; as, for example, an
intention to pass counterfeit bank notes, knowing them to be counterfeit. 1
Car. Law Rep. 517.
     6.-2. In order to make a contract, there must, be an intention to
make it a person non compos mentis, who has no contracting mind, cannot,
therefore, enter into any engagement which requires an intention; for to
make a contract the law requires a fair, and serious exercise of the
reasoning faculty. Vide Gift; Occupancy.
     7.-3. In wills and testaments, the intention of the testator must be
gathered from the whole instrument; 3 Ves. 105; and a codicil ought to be
taken as a part of the will; 4 Ves. 610; and when such intention is
ascertained, it must prevail, unless it be in opposition to some unbending
rule of law. 6 Cruise's Dig. 295; Rand. on Perp. 121; Cro. Jac. 415. " It is
written," says Swinb. p. 10, " that the will or meaning of the testator is
the queen or empress of the testament; because the will doth rule the
testament, enlarge and restrain it, and in every respect moderate and direct
the same, and is, indeed, the very efficient cause. thereof. The will,
therefore, and meaning of the testator ought, before all things, to be
sought for diligently, and, being found, ought to be observed faithfully." 6
Pet. R. 68. Vide, generally, Bl. Com. Index, h. t.; 2 Stark. Ev. h. t.; A 1.
Pand. 95; Dane's Ab. Index h. t.; Rob. Fr. Conv. 30. As to intention in
changing a residence, see article Inhabitant.



The Devil's Dictionary (1881-1906):

INTENTION, n.  The mind's sense of the prevalence of one set of
influences over another set; an effect whose cause is the imminence,
immediate or remote, of the performance of an involuntary act.