tontine

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An investment plan in which participants buy shares in a common fund and receive an annuity that increases every time a participant dies, with the entire fund going to the final survivor or to those who survive after a specified time.
• noun Each member's share of a tontine.
• noun The subscribers to a tontine.

from The Century Dictionary.

• noun An annuity shared by subscribers to a loan, with the benefit of survivorship, the share of each survivor being increased as the subscribers die, until at last the whole goes to the last survivor, the whole transaction ceasing with his death.
• Of, pertaining to. constituting, or involving the principle of the tontine; as, tontine profits; tontine funds; tontine insurance.

from the GNU version of the Collaborative International Dictionary of English.

• noun An annuity, with the benefit of survivorship, or a loan raised on life annuities with the benefit of survivorship. Thus, an annuity is shared among a number, on the principle that the share of each, at his death, is enjoyed by the survivors, until at last the whole goes to the last survivor, or to the last two or three, according to the terms on which the money is advanced. Used also adjectively.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun finance, insurance A form of investment in which, on the death of an investor, his share is divided amongst the other investors.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an annuity scheme wherein participants share certain benefits and on the death of any participant his benefits are redistributed among the remaining participants; can run for a fixed period of time or until the death of all but one participant
• noun a form of life insurance whereby on the death or default of a participant his share is distributed to the remaining members