A rounder is a skilled card shark who makes his/her living entirely at playing cards. This the most common use of the word.

The term "rounder" carries a certain respect amongst card players, as they know anyone with that title knows their way around a table and is a person to be taken seriously, unlike the opposite of a rounder, a "fish." The term sometimes also implies a player making a living by "hustling" less experienced players in games during their "rounds".

Some noted rounders include Doyle Brunson, Amarillo Slim, and Sailor Roberts. A movie about poker titled Rounders was made in 1998, starring Matt Damon and Edward Norton.

• A score in a game of rounders.