Enter a clue or pattern or both:
The Clue
Slip of paper in a poker pot (3 letter answer)
The Answer
IOU
Tags
Notes
The answer IOU is seen frequently, appearing about once every 90 puzzles.
Related Clues
Chit
Marker
Beholden letters
Commitment to pay
Debt acknowledgment
Debt chit
Debt doc
Debt letters
Debt marker
Debtor's letters
Debtor's note
Gambler's mark
Gambler's note
Letters on a chit
Letters of credit
Letters of credit?
Marker letters
Marker, for short
Obligation of a sort
Paper in a pot
Payment initials
Promise to pay
Promissory note
Slip in a pot
Item in a poker pot
Losing gambler's mark
Marker in a poker pot
Paper in a poker pot
Part of a poker pot
Last poker bet, sometimes
Note in a poker game, e.g.
Poker game memento, maybe
Definition
IOU as a noun:
1. an informal debt instrument; representing `I owe you'