Source : Webster's Revised Unabridged Dictionary (1913)

Godless \God"less\, a.
   Having, or acknowledging, no God; without reverence for God;
   impious; wicked. -- {God"less*ly}, adv. -- {God"less*ness},
   n.

Source : WordNet®

godlessness
     n 1: the doctrine or belief that there is no God [syn: {atheism}]
          [ant: {theism}]
     2: impiety by virtue of not being a godly person [syn: {ungodliness}]
        [ant: {godliness}]