See flavorless in Webster's New World Roget's A-Z Thesaurus II
adjective
Lacking an appetizing flavor:
bland, flat, insipid, tasteless, unsavory. See tasteLacking liveliness, charm, or surprise:
arid, aseptic, colorless, drab, dry, dull, earthbound, flat, lackluster, lifeless, lusterless, matter-of-fact, pedestrian, prosaic, spiritless, sterile, stodgy, unimaginative, uninspired. See excite
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