The Collaborative International Dictionary of English v.0.48:

Contribution \Con`tri*bu"tion\, n. [L. contributio: cf. F.
   contribution.]
   1. The act of contributing.
      [1913 Webster]

   2. That which is contributed; -- either the portion which an
      individual furnishes to the common stock, or the whole
      which is formed by the gifts of individuals.
      [1913 Webster]

            A certain contribution for the poor saints which are
            at jerusalem.                         --Rom. xv. 26.
      [1913 Webster]

            Aristotle's actual contributions to the physical
            sciences.                             --Whewell.
      [1913 Webster]

   3. (Mil.) An irregular and arbitrary imposition or tax leved
      on the people of a town or country.
      [1913 Webster]

            These sums, . . . and the forced contributions paid
            by luckless peasants, enabled him to keep his
            straggling troops together.           --Motley.
      [1913 Webster]

   4. (Law) Payment, by each of several jointly liable, of a
      share in a loss suffered or an amount paid by one of their
      number for the common benefit.
      [1913 Webster]

WordNet (r) 3.0 (2006):

contribution
    n 1: the part played by a person in bringing about a result; "I
         am proud of my contribution in advancing the project";
         "they all did their share of the work" [syn:
         contribution, part, share]
    2: a voluntary gift (as of money or service or ideas) made to
       some worthwhile cause [syn: contribution, donation]
    3: act of giving in common with others for a common purpose
       especially to a charity [syn: contribution, donation]
    4: an amount of money contributed; "he expected his contribution
       to be repaid with interest"
    5: a writing for publication especially one of a collection of
       writings as an article or story

Moby Thesaurus II by Grady Ward, 1.0:

120 Moby Thesaurus words for "contribution":
   accommodation, accordance, alms, alms fee, assessment, association,
   award, awarding, benefaction, beneficence, bestowal, bestowment,
   blackmail, call, call for, cess, chanty, charity, claim,
   cochairmanship, collection, communication, complicity, concession,
   condominium, conferment, conferral, conscience money,
   copartnership, copartnery, cotenancy, deliverance, delivery,
   demand, demand for, direct tax, dole, donation, donative, draft,
   drain, duty, endowment, engagement, exaction, extortion,
   extortionate demand, furnishment, gifting, giving,
   graduated taxation, grant, granting, handout, having a part,
   heavy demand, impartation, impartment, imposition, impost, indent,
   indirect tax, insistent demand, investiture, involvement,
   joint chairmanship, joint control, joint ownership, joint return,
   joint tenancy, levy, liberality, nonnegotiable demand, notice,
   offer, offering, offertory, order, partaking, participation,
   partnership, pittance, presentation, presentment, progressive tax,
   provision, requirement, requisition, rush, rush order,
   separate returns, sharing, single tax, subscription, suffrage,
   supertax, supplying, surrender, surtax, tax, tax base, tax dodging,
   tax evasion, tax exemption, tax return, tax structure,
   tax withholding, tax-exempt status, taxable income, taxation,
   taxing, tithe, toll, tribute, ultimatum, voting, votive offering,
   vouchsafement, warning, withholding tax



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

CONTRIBUTION, civil law. A partition by which the creditors of an insolvent
debtor divide, among themselves the proceeds of his property, proportionably
to the amount of their respective credits. Civ. Code of Lo. art. 2522, n.
10. It is a division pro rata. Merl. Rep. h.t.



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

CONTRIBUTION, contracts. When two or more persons jointly owe a debt, and
one is compelled to pay the whole of it, the others are bound to indemnify
him for the payment of their shares; this indemnity is called a
contribution. 1 Bibb. R. 562; 4 John. Ch. R. 545; 4 Bouv. Inst. n. 3935-6.
     2. The subject will be considered by taking a view, 1. Of right of the
creditors where there are several debtors. 2. Of the right of the debtor who
pays the whole debt. 3. Of the liabilities of the debtors who are liable to
contribution. 4. Of the liability of land owned by several owners, when it
is subject to a charge. 5. Of the liability of owners of goods in a vessel,
when part is thrown overboard to save the rest.
     3.-1. The creditor of several debtors, jointly bound to him, has a
right to compel the payment by any he may choose; but he cannot sue them
severally, unless they are severally bound.
     4.-2. When one of several debtors pays a debt, the creditor is bound
in conscience, if not by contract, to give to the party paying the debt all
his remedies against the other debtors. 1 Cox, R. 318 S. C. 2 B. & P. 270 2
Swanst. R. 189, 192; 3 Bligh, 59 14 Ves. 160; 1 Ves. 31 12 Wheat. 596 1
Hill, Ch. R. 844, 351 1 Term. St. It. 512, 517; 1 Ala. R. 23, 28; 11 Ohio
It. 444, 449 8 Misso. It. 169, 175.
     5.- 3. A debtor liable to contribution is not responsible upon a
contract, but is so in equity. But courts of common law, in modern times,
have assumed a jurisdiction to compel contribution among sureties, in the
absence of any positive contract, on the ground of an implied assumpsit, and
each of the sureties may be sued for his respective quota or proportion.
White's L. C. in Eq. 66. The remedy in equity is, however, much more
effective. For example, a surety who pays an entire debt, can, in equity,
compel the solvent sureties to contribute towards the payment of the entire
debt. 1 Chan. R. 34 1 Chan. Cas. 246; Finch, R. 15, 203. But at law he can
recover no more than an aliquot part of the whole, regard being had to the
number of co-sureties. 2 B. & P. 268; 6 B. & C. 697.
     6.-4. When land is charged with the payment of a legacy, or an estate
with the portion of a posthumous child, every part is bound to make
contribution. 3 Munf. R. 29; 1 John. Ch. R. 425 2 Bouv. Inst. n. 1301.
     7.-5. Contribution takes place in another case; namely, when in order
to save a ship or cargo, a part of the goods are cast overboard, the ship
and cargo are liable to contribution in order to indemnify the owner of the
goods lost, except his just proportion. No contribution can be claimed
between joint wrong doers. Bac. Ab. Assumpsit A; Vide 3 Com. Dig. 143; 8
Com. Dig. 373; 5 Vin. Ab. 561; 2 Supp. to Ves. jr. 159, 343; 3 Ves. jr. 64;
Wesk. Ins. 130; 10 S. & R. 75; 5 B. & Ad. 936; S. C. 3 N. & M. 258; Rast.
Entr. 161; 2 Ventr. 348; 2 Vern. 592; 2 B. & P. 268; 3 B. & P 235; 5 East,
225; 1 J. P. Smith 411 5 Esp. 194; 3 Campb. 480; Gow, N. P. C. 13; 2 A. & E.
57; 4 N. & M. 64; 6 N. & M. 494.