Faithless

Faith·less

Faithless

a.
  1. Not believing; not giving credit.
    Be not faithless, but believing.
    — John xx. 27.
  2. Not believing on God or religion; specifically, not believing in the Christian religion.
  3. Not observant of promises or covenants.
  4. Not true to allegiance, duty, or vows; perfidious; trecherous; disloyal; not of true fidelity; inconstant, as a husband or a wife.
    A most unnatural and faithless service.
  5. Serving to disappoint or deceive; delusive; unsatisfying.