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Often confused with palette or pallet, palate refers to the roof of the mouth. A second definition is a person's appreciation of taste and flavor, especially when sophisticated and discriminating.

Middle English acquired palate from Latin "palatum."

Dictionary.com has an entire article on Palette/Pallet/Palate.

I see also that palate was also used for the vault of a chamber, and that it may go back to Etruscan.