Definitions
1.adjectiveLacking faith; lacking belief in something.
2.adjectiveNot believing in God, religion, or a comparable ideology.
3.adjectiveUnfaithful (said of people, towards their partners)
4.adjectiveNot observant of promises or covenants.
5.adjectiveNot true to allegiance, duty, or vows
6.adjectiveServing to disappoint or deceive