irredeemable
adjective
uk/ˌɪrɪˈdiːməbl/ usimpossible to correct, improve, or change:
An irredeemable letter cannot be cancelled.
FINANCE
used to describe investments such as bonds that pay interest but have no agreed date on which the borrower must pay the lender:
They may be irredeemable, so that although they can be sold at any time the capital realised will depend on their price in the open market.
irredeemable
noun
uk/ˌɪrɪˈdiːməbl/ usirredeemables
[ plural ] FINANCE
bonds that pay interest but have no agreed date on which the borrower must pay the lender:
Irredeemables have no redemption date at all, so that interest on them will be paid indefinitely.