A flush is a description for a specific type of hand (i.e. set of cards) in a poker card game. You have a flush if you have five cards of the same suit in your hand. So, for example, if you had five cards that were all hearts then you would have a flush. This is a fairly high ranking hand in itself in standard terms but variations of the hand rank higher than others.

The standard flush variations possible in a game of poker include:

Some non-standard poker games will use the word flush to denote other hands. So, for example, in some games four cards of the same suit may be referred to as a four flush or a bobtail flush. A flush house may also be used in certain types of poker game to describe a hand that is composed of three cards of one suit and two cards of another suit.