The Collaborative International Dictionary of English v.0.48:

Annuity \An*nu"i*ty\, n.; pl. Annuities. [LL. annuitas, fr. L.
   annus year: cf. F. annuit['e].]
   A sum of money, payable yearly, to continue for a given
   number of years, for life, or forever; an annual allowance.
   [1913 Webster]

WordNet (r) 3.0 (2006):

annuity
    n 1: income from capital investment paid in a series of regular
         payments; "his retirement fund was set up to be paid as an
         annuity" [syn: annuity, rente]

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "annuity":
   accident insurance, actuary, aid, alimony, allotment, allowance,
   assistance, assurance, aviation insurance, bail bond, bond, bounty,
   business life insurance, casualty insurance,
   certificate of insurance, court bond, credit insurance,
   credit life insurance, deductible, depletion allowance, dole,
   endowment insurance, family maintenance policy, fellowship,
   fidelity bond, fidelity insurance, financial assistance,
   flood insurance, fraternal insurance, government insurance, grant,
   grant-in-aid, guaranteed annual income, health insurance, help,
   industrial life insurance, insurance, insurance agent,
   insurance broker, insurance company, insurance man,
   insurance policy, interinsurance, liability insurance,
   license bond, limited payment insurance, major medical insurance,
   malpractice insurance, marine insurance, mutual company,
   ocean marine insurance, old-age insurance, pecuniary aid, pension,
   permit bond, policy, price support, public assistance,
   public welfare, relief, retirement benefits, robbery insurance,
   scholarship, social security, stipend, stock company,
   subsidization, subsidy, subvention, support, tax benefit,
   term insurance, theft insurance, underwriter, welfare, welfare aid,
   welfare payments



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

ANNUITY, contracts. An annuity is a, yearly sum of money granted by one party

to another in fee for life or years, charging the person of the grantor
only. Co. Litt. 144; 1 Lilly's Reg. 89; 2 Bl. Com. 40; 5 M. R. 312; Lumley
on Annuities. 1; 2 Inst. 293; Davies' Rep. 14, 15.

     2. In a less technical sense, however, when the money is chargeable on
land and on the person, it is generally called an annuity. Doet. and Stud
Dial. 2, 230; Roll. Ab. 226. See 10 Watts, 127.
     3. An annuity is different from a rent charge, with which it is
frequently confounded, in this; a rent charge is a burden imposed upon and
issuing out of lands, whereas an annuity is chargeable only upon the person
of the grantee. Bac. Abr. Annuity, A. See, for many, regulations in England
relating to annuities, the Stat,. 17 Geo. III. c. 26.
     3. An annuity may be created by contract, or by will. To enforce the
payment of an annuity, the common law gives a writ of annuity which may be
brought by the grantee or his heirs, or their grantees, against the grantor
and his heirs. The action of debt cannot be maintained at the common law, or
by the Stat. of 8 Anne, c. 14, for the arrears of an annuity devised to A,
payable out of lands during the life of B, to whom the lands are devised for
life, B paying the annuity out of it, so long as the freehold estates
continues. 4 M. & S. 113; 3 Brod. & Bing. 30; 6 Moore, 336. It has been
ruled also, that if an action of annuity be brought, and the annuity
determines pending the suit, the writ faileth forever because no such action
is maintainable for arrearages only, but for the annuity and the arrearages.
Co. Litt. 285, a.
     4. The first payment of an annuity is to be made at the time appointed
in the instrument creating it. In cases where testator directs the annuity
to be paid at the end of the first quarter, or other period before the
expiration of the first year after his death, it is then due; but in fact it
is not payable by the executor till the end of the year. 3 Mad. Ch. R. 167.
When the time is not appointed, as frequently happens in will, the following
distinction is presumed to exist. If the bequest be merely in the form of an
annuity as a gift to a man of "an annuity of one hundred dollars for life"
the first payment will be due at the end of the year after the testator's
death. But if the disposition be of a sum of money, and the interest to be
given as an annuity to the same man for life, the first payment will not
accrue before the expiration of the second year after the testator's death.
This distinction, though stated from the bench, does not appear to have been
sanctioned by express decision. 7 Ves. 96, 97.
     5. The Civil Code of Louisiana makes the following provisions in
relation to annuities, namely: The contract of annuity is that by which one
party delivers to another a sum of money, and agrees not to reclaim it, so
long as the receiver pays the rent agreed upon. Art. 2764.
     6. This annuity may be perpetual or for life. Art. 2765.
     7. The amount of the annuity for life can in no case exceed the double
of the conventional interest. The amount of the perpetual annuity cannot
exceed the double of the conventional interest. Art. 2766.
     8. Constituted annuity is essentially redeemable. Art. 2767.
     9. The debtor of a constituted annuity may be compelled to redeem the
same: 1, If he ceases fulfilling his obligations during three years: 2, If
he does not give the lender the securities promised by the contract. Art.
2768.
    10. If the debtor should fail, or be in a state of insolvency, the
capital of the constituted annuity becomes exigible, but only up to the
amount at which it is rated, according to the order of contribution amongst
the creditors. Art. 2769.
    11. A similar rule to that contained in the last article has been
adopted in England. See stat. 6 Geo. IV., c. 16, s. 54 and 108; note to Ex
parte James, 5 Ves. 708; l Sup. to Ves. Jr. 431; note to Franks v. Cooper, 4
Ves. 763; 1 Supp. to Ves. Jr. 308. The debtor, continues the Code, may be
compelled by his security to redeem the annuity within the time which has
been fixed in the contract, if any time has been fixed, or after ten years,
if no mention be made of the time in the act. Art. 2770.
    12. The interest of the sums lent, and the arrears of constituted and
life annuity, cannot bear interest but from the day a judicial demand of the
same has been made by the creditor, and when the interest is due for at
least one whole year. The parties may only agree, that the same shall not be
redeemed prior to a time which cannot exceed ten years, or without having
warned the creditor a time before, which they shall limit. Art. 2771. See
generally, Vin. Abr. Annuity; Bac. Abr. Annuity and Rent; Com. Dig. Annuity;
8 Com. Dig. 909; Doct. Plac. 84; 1 Rop. on Leg. 588; Diet. de Jurisp. aux
mots Rentes viageres, Tontine. 1 Harr. Dig. h.t.