Sheets might be placed in them

OVENS

Think of where you’d bake something flat and thin, like cookies or pizza—these appliances get quite hot inside.

The clue plays on the double meaning of "sheets." While we usually think of sheets as bedding, in baking, "sheets" can refer to flat trays used for cookies or pastries. These trays are placed in ovens, so the answer is "OVENS"—the wordplay hinges on the less common use of "sheets" in a kitchen context. It’s a clever twist that makes you reconsider the everyday word.