Item that has to be blown up before being filled with water

INFLATABLEPOOL

"Hint: "It's a backyard summer staple that needs air before it can hold any liquid." This hint guides the solver toward thinking of common outdoor items that require inflation and are associated with water, without directly stating the answer."

Clue: "Item that has to be blown up before being filled with water" Answer: "INFLATABLEPOOL" Explanation: The clue plays on the dual meaning of "blown up." Literally, an inflatable pool must be inflated (or "blown up") with air before it can be filled with water.