The term “playing the board” can be used to describe a situation where a No-limit Hold’em player does not use 9️⃣ any of his hole-cards to formulate a hand. Imagine the board reads as follows:
Board: T♠J♠Q♣K♣A♦
This is an example where all 9️⃣ players at the table are forced to “play the board”. This is because it is impossible to improve on the 9️⃣ strength of an Ace-to-Ten straight by utilizing hole-cards.
Playing the board applies mostly to Hold’em, since playing the board in variants 9️⃣ such as Omaha is mostly impossible. This is due to the “tight hold’em” rule which forces players to always use 9️⃣ exactly two of their hole-cards when formulating a hand in Omaha. On the above board texture, Omaha players would need 9️⃣ to have two cards between Ace and Nine in order to make a straight (not including A9xx).
Example of Board used 9️⃣ in a sentence -> We open raised preflop in Hold’em and the board came down Ace-high dry.