When a player makes a blind bet, they are making a bet without looking at their cards. Blind bets are a common occurrence in lowball poker, as they often help stimulate the action.
Sometimes players claim to bet blind but actually have seen their cards, which is considered poor poker etiquette.
Another definition of a blind bet applies to community poker games, in which these bets are mandatory for players to place before the cards are dealt. This could be either in addition or instead of the ante.