Pinochle pronounced [pEŽnuŽŽkul] is a card game, that was developed in the United States in the 19th century. Pinochle is played by two, three, or four players, with a deck of 48 cards containing two each of the aces, face cards, tens, and nines of all four suits. The cards rank (in descending order) ace, ten, king, queen, jack, and nine. In all forms of pinochle, an arbitrary point goal is often set, e.g., 1,000 points, instead of just playing for game.

Auction pinochle, probably the most popular form of the game, is played by three persons at a time, although up to six may play in rotating units of three. Each of the three active players is dealt a hand of 15 cards, three at a time, and three are dealt face down in the center of the table, forming the "widow." Bidding starts at 300 points (lower in some cases) and progresses in rotation by minimum 10-point advances. Once a player passes he may not bid again. Two passes end the auction, and the highest bidder wins.

In two-handed pinochle 12 cards are dealt to each player, a card is turned up to determine trump suit, and players may meld after each trick won. Thus meld and play continue concurrently until the stock is used up: after which play continues until the last 12 cards in the hand are exhausted: and the highest combined score of meld and tricks wins.

Four-hand, or partnership pinochle may be played on an auction basis : in which case each member receives 12 cards and bids for the right to meld and name trump. After melding, the bidder joins forces with his partner in play against the other set of partners.

Another form of partnership pinochle is played by opening the bottom card to determine trump. All four players meld before the opening trick is led.