English Theasurus that shows all the ways the English word is translated from the original Greek and Hebrew.
English Theasurus from the Hebrew and Greek Strong's Dictionary
unfaithfully 0898 -- bagad -- deal deceitfully (treacherously, {unfaithfully}),offend, transgress(-or), (depart), treacherous (dealer, -ly, man),unfaithful(-ly, man), X very.