(sports) To show someone a yellow card

(transitive, sports) To show (a player) a red card, and dismiss them from the playing area; to send off.

A greeting card given to someone to celebrate his or her birthday.

(US) A US work permit, officially known as United States Permanent Resident Card.

A person who uses card counting in pontoon or blackjack in order to obtain an advantage.

A strategy, in pontoon or blackjack, in which a player keeps a mental tally of the cards played in order to calculate the probability of certain cards being dealt and therefore obtain an advantage.

plural of green card

plural of red card

A playing card, of the trump suit that is held in reserve until needed to win a trick. / Something used to obtain an advantage, sometimes unscrupulously.

A pamphlet accompanying a CD, film etc., summarising the contents and production.