The Collaborative International Dictionary of English v.0.48:
Antediluvial \An`te*di*lu"vi*al\ ([a^]n`t[-e]*d[i^]*l[=u]"v[i^]*al), a. [Pref. ante- + diluvial.] Before the flood, or Deluge, in Noah's time. [1913 Webster]WordNet (r) 3.0 (2006):
antediluvial adj 1: of or relating to the period before the biblical flood; "antediluvian man" [syn: antediluvian, antediluvial]