Answer:

IOU

Answer	Crossword Clue
IOU	Debt note
IOU	Debtor's letters
IOU	Marker

IOU	Account receivable
IOU	Letters of debt
IOU	Promising letters
IOU	Promising note?
IOU	Letters for those in the red
IOU	Promise to pay
IOU	Informal credit, informally
IOU	Letters for one in the red

IOU	Promise from a short person?
IOU	Promise of payback
IOU	Letters for a bettor who'll do better next time
IOU	Debt statement
IOU	Chit
IOU	Payment proxy
IOU	Payment promise
IOU	Slip among chips?

IOU	"Will pay later"
IOU	Bettor's letters
IOU	Payment pledge
IOU	Borrower's pledge
IOU	Debt "forgiven" in eight theme entries
IOU	"Got you next time" letters
IOU	Poker pot note
IOU	Debt letters

IOU	It's exchanged for cash
IOU	Slip in a pot
IOU	Questionable pot addition
IOU	Personal marker
IOU	Gambler's marker
IOU	Letters written before a dollar amount, sometimes
IOU	Debt to be paid
IOU	Debtor's promise

IOU	Letters of credit
IOU	Letters on a note
IOU	Signed note
IOU	Debt acknowledgement
IOU	Something to pay