1. hostile or indifferent to religion
The Collaborative International Dictionary of English v.0.48:
Irreligious \Ir`re*li"gious\, a. [L. irreligiosus: cf. F.
1. Destitute of religion; not controlled by religious motives
or principles; ungodly. Cf. Impious.
Shame and reproach are generally the portion of the
impious and irreligious. --South.
2. Indicating a lack of religion; profane; wicked; as,
WordNet (r) 3.0 (2006):
adj 1: hostile or indifferent to religion [ant: religious]
Moby Thesaurus II by Grady Ward, 1.0:
47 Moby Thesaurus words for "irreligious":
amoral, apostate, atheistic, backsliding, blasphemous, creedless,
disbelieving, faithless, fallen, fallen from grace, godless,
heretical, impious, incredulous, indevout, irreverent, lapsed,
minimifidian, nonbelieving, nonreligious, nullifidian, profanatory,
profane, recidivist, recidivistic, recreant, renegade, repudiative,
sacrilegious, sinful, un-Christly, unangelic, unbelieving,
unchristian, unconfident, unconverted, unconvinced, undevout,
undutiful, ungodly, unholy, unmoral, unreligious, unrighteous,
unsaintly, wicked, without faith