perfidiously

/pərˈfɪdiəsli/
adverb
  1. In a way that is deliberately dishonest and betraying trust.
    • She perfidiously revealed her friend's secret to the whole class.
    • The company perfidiously broke its promise to its employees.
    • The general acted perfidiously by switching sides during the battle.
Antonyms
What does "perfidiously" mean? | whatsthatwordmean | whatsthatwordmean