Merriam-Webster Collegiate Dictionary - insipid

 adjective  Etymology: French & Late Latin; French ~e, from Late Latin ~us, from Latin in- + sapidus savory, from sapere to taste — more at sage  Date: 1609  1. lacking taste or savor ; tasteless ~ food  2. lacking in qualities that interest, stimulate, or challenge ; dull, flat ~ prose  • ~ity noun  • ~ly adverb Synonyms:  ~, vapid, flat, jejune, banal, inane mean devoid of qualities that make for spirit and character. ~ implies a lack of sufficient taste or savor to please or interest an ~ romance with platitudes on every page. vapid suggests a lack of liveliness, force, or spirit an exciting story given a vapid treatment. flat applies to things that have lost their sparkle or zest although well-regarded in its day, the novel now seems flat. jejune suggests a lack of rewarding or satisfying substance a jejune and gassy speech. banal stresses the complete absence of freshness, novelty, or immediacy a banal tale of unrequited love. inane implies a lack of any significant or convincing quality an inane interpretation of the play.