Having lost its life and spirit; dead; spiritless; insipid; flat; dull; unanimated; as, vapid beer; a vapid speech; a vapid state of the blood. A cheap, bloodless reformation, a guiltless liberty, appear flat and vapid to their taste. (Burke) Vapidly, Vapidness.
Origin: L. Vapidus having lost its lire and spirit, vapid; akin to vappa vapid wine, vapor vapor. See Vapor.