The Collaborative International Dictionary of English v.0.48:
Vapidity \Va*pid"i*ty\, n. The quality or state of being vapid; vapidness. [1913 Webster]WordNet (r) 3.0 (2006):
vapidity n 1: the quality of being vapid and unsophisticated [syn: jejunity, jejuneness, tameness, vapidity, vapidness]