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tongue map

n. A schematic map of the human tongue, labelling which parts are (supposedly) receptive to different tastes.

Wikipedia
Tongue map

The tongue map or taste map is a common misconception that different sections of the tongue are exclusively responsible for different basic tastes. It is illustrated with a schematic map of the tongue, with certain parts of the tongue labeled for each taste. Although widely taught in schools, this was scientifically disproven by later research; all taste sensations come from all regions of the tongue, although different parts are more sensitive to certain tastes.