"Then away goes the brisk and pleasant Spirits and leave a vapid or sour Drink." So wrote John Mortimer—an early 18th-century expert on agriculture, orchards, and cider-making—in his book on husbandry. His use was typical for his day, when vapid was often used specifically in reference to liquor. The term comes from Latin vapidus, meaning "flat-tasting," a possible relative of vapor. That use still occurs today; you might, for example, hear an uninspiring wine described as vapid. More likely you'll hear vapid, along with the synonyms insipid, flat, and inane, describe people and things that lack spirit and character.