A spelling bee word I have seen before, but never looked up.
debenture
n.
5ME debentur < ML < L, 3d pers. pl., pres. pass. indic., of debere: see DEBT: so called from receipts beginning with the Latin words debentur mihi, there are owing to me6
1 a voucher or certificate acknowledging that a debt is owed by the signer
2 a customhouse order for payment of a drawback, as to an importer
3 an interest-bearing bond issued against the general credit of a corporation or governmental unit, with no specific pledge of assets