irreligion

from WordNet (r) 3.0 (2006)

irreligion
    n 1: the quality of not being devout [syn: {irreligiousness},
         {irreligion}]

from The Collaborative International Dictionary of English v.0.48

Irreligion \Ir`re*li"gion\, n. [L. irreligio: cf. F.
   irr['e]ligion. See {In-} not, and {Religion}.]
   The state of being irreligious; lack of religion; impiety.
   [1913 Webster]

from The Devil's Dictionary (1881-1906)

IRRELIGION, n.  The principal one of the great faiths of the world.

from Moby Thesaurus II by Grady Ward, 1.0

23 Moby Thesaurus words for "irreligion":
      apostasy, atheism, backsliding, desertion, fall from grace,
      godlessness, impiety, impiousness, irreverence, lapse,
      lapse from grace, recidivism, recreancy, sinfulness,
      un-Christliness, unangelicalness, unchristianliness, undutifulness,
      ungodliness, unholiness, unrighteousness, unsaintliness,
      wickedness

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