Euchre or eucre is a trick-taking card game commonly played in Australia, Canada, Great Britain, New Zealand, and the Midwestern United States. It is played with a deck of 24, 25, 28, or 32 standard playing cards. There are normally four players, two on each team, although there are variations for two to nine players.

A trick-taking game is a card or tile-based game in which play of a hand centers on a series of finite rounds or units of play, called tricks, which are each evaluated to determine a winner or taker of that trick. The object of such games then may be closely tied to the number of tricks taken, as in plain-trick games such as contract bridge, whist, and spades, or to the value of the cards contained in taken tricks, as in point-trick games such as pinochle, the tarot family, briscola, and most evasion games like hearts. Trick-and-draw games are trick-taking games in which the players can fill up their hands after each trick. In most variants, players are free to play any card into a trick in the first phase of the game, but must follow suit as soon as the stock is depleted. Trick-avoidance games like reversis or polignac are those in which the aim is to avoid taking some or all tricks.