In card games, hand has three related meanings. It can be the cards a player holds, the complete round from the deal to the payout, or the rank of the cards, such as a pair or a flush. In poker, the best five card hand wins. In blackjack, a hand is the cards in front of a player, and one player can have several hands after splitting. When statistics refer to hands per hour, they mean full rounds played.
Example
A blackjack player dealt two 8s splits them and now plays two hands at once, each with its own bet.