Pronunciation: /pərˈfɪdiəs/
adjective deceitful and untrustworthy
A1 I heard a story about a perfidious friend who betrayed his best friend.
A2 The perfidious villain pretended to be the hero's ally before revealing his true intentions.
B1 The perfidious politician promised to lower taxes during the campaign, but raised them once in office.
B2 The perfidious spy leaked classified information to the enemy, putting national security at risk.
C1 The perfidious CEO embezzled millions of dollars from the company, leading to its downfall.
C2 The perfidious dictator used propaganda and deceit to maintain power over his oppressed people.
formal The perfidious actions of the traitor were revealed during the investigation.
informal I can't believe she would be so perfidious as to betray her best friend like that.
slang That perfidious snake stabbed me in the back when I least expected it.
figurative The storm clouds gathered, a perfidious omen of the trouble to come.
perfidiously
perfidiouses
more perfidious
most perfidious
perfidies
will be perfidious
have been perfidious
is being perfidious
perfidious
perfidious
to be perfidious
perfidiously
perfidiousing