Synonyms and related words :
dead, dilute, diluted, fade, flat, flavorless, gruelly, inane, indifferent, insipid, jejune, mild, milk-and-water, pappy, pulpy, sapless, savorless, stale, tasteless, thin, unflavored, unsavory, vapid, washy, watered, watered-down, watery, weak, wishy-washy