In poker, an extra blind usually refers to an additional mandatory bet which one or more players place before the cards are dealt, alongside the standard small and big blinds.

Extra blinds can be used in various poker formats and in various situations, for example:

Third blind:

In some types of poker, usually home games, a third blind may be used, which is usually posted by the player sitting to the left of the big blind.

Straddle:

A straddle is an additional bet which can be placed by the player sitting to the left of the big blind before the cards are dealt. A straddle is usually twice as large as the big blind and gives the player the final say on the preflop.

Re-straddle:

A re-straddle is another additional bet which may be placed by the player to the left of the player who placed the straddle. A re-straddle is usually twice as large as the straddle.

Ante:

Though the ante is not a blind, it is a mandatory bet which is placed by all the players before the cards are dealt. An ante is used in addition to blinds to increase the size of the pot.

Additional blinds add extra strategic depth and may increase aggression and betting sizes in the game.