Lacking flavor or having no taste; can also mean lacking aesthetic or moral sensitivity.
From Old English 'taste' (possibly from Old French 'taster') plus 'less' (without); both the literal and figurative meanings developed by the 1600s.
Tasteless works on two levels—you can have food with no taste buds triggered, or art with no aesthetic appeal—and this duality shows how humans map physical sensations onto abstract judgments constantly.
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