The upper portion of the inside of the mouth. More commonly and incorrectly referred to as the "roof" of the mouth. This doesn't make sense because it's inside, like a ceiling, not outside, like a roof. The scalp and hair are the roof of your head, and your mouth has a ceiling.
Jim: "Hey Dan, want some tortilla chips or some Captain Crunch?"

Dan: "No thanks. Last night, I made a pizza in the oven, and like an idiot, I bit into a piece right away. The hot cheese burned the ceiling of my mouth. It hurts. I need to eat apple sauce for a few days".
by orangek July 20, 2011
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