A promise to set aside, dedicate and use exclusively for specified purposes certain categories of property, generally money or other intangibles.
See Also
A covenant that is the opposite of a pledge – a promise not to pledge property, generally money or other intangibles, to any party other than the issuer, a letter of credit provider or other intended beneficiary of the negative pledge.

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A contract between an issuer and a trustee under which the issuer issues bonds and specifies their maturities, interest rates, redemption provisions, form, exchange provisions, security and other terms.