Index
An index is the number or letter printed on the corner of a card. A cheater can also add an index, which is a mark on the edge of a card.
The simple explanation
On every card, the rank and suit are printed in the corner. That is the index. You can read the card by it when you hold the cards in a fan.
A closer look
The word also appears in cheating: marks put on the edge of cards are called indexing, and they let the cheater recognize the card from behind. Large indexes are useful for players with poor eyesight, and four-color decks use different colors for the suits to make them even clearer.
A practical example
A player looks at the index in the corner of his card and sees a king.
Full explanation
An index is the number or letter printed on the corner of a card. A cheater can also add an index, which is a mark on the edge of a card.
An index is the rank and suit mark in a card’s corner.
A cheater’s mark on the edge is also called an index.
Large indexes help you read cards.
See also indexing and marked cards.