perfidious - Master This Word
Master this word with our 5-step learning method – Learn English in English
perfidious Word Meanings
- deceitful and untrustworthy
- betraying trust
- disloyal or treacherous
perfidious Example Sentences
Example sentences are the start of understanding. Don't rush to memorize. First feel how the word works in a sentence.
perfidious Phonetic & Pronunciation
UK
/pərˈfɪd.i.əs/
US
/pərˈfɪd.i.əs/
perfidious Word Etymology
per- = through + fides = faith; Latin → Old French → English. Imagine a treacherous friend whispering sweet nothings while plotting betrayal behind your back, representing the deceit at the heart of 'perfidious'.
Note 1: These definitions and etymologies are not standard dictionary definitions, but extended explanations provided to help with memorization and understanding of the actual application of words. Through this background information, we strive to make words more vivid and easier to understand, and help you remember their meanings in real life.
Note 2: LexiTalk designs the learning flow around the linguistics principle of “Comprehensible Input.” When learners encounter material that is slightly above their level but still understandable from context, the brain naturally absorbs the language. That’s why we keep every word inside authentic contexts, using examples and associations to help you understand it and use it flexibly.
Read the FAQ explanation of Comprehensible InputReal Context
Perfidious refers to deceitful and treacherous behavior that betrays trust in a calculated, often subtle way. It describes someone who appears loyal or friendly on the surface but secretly acts against you, breaking confidences, obligations, or promises. The word carries a sharper moral condemnation than ordinary lying, implying a deliberate preference for personal gain over keeping faith. You might call a treacherous ally or a betrayed confidant perfidious. In historical or literary contexts, perfidious enemies are depicted as charming, persuasive, and untrustworthy, never to be trusted again. Remember the etymology: through faith; the idea is betrayal of a bond that ought to be sacred. Use perfidious to emphasize calculated betrayal rather than mere incompetence.
Usage Reminders
- Is used for deliberate betrayal, not ordinary lying.
- Carries strong moral condemnation.
- Typically describes someone who pretends loyalty while plotting harm.
- Not interchangeable with casual 'dishonest' in formal writing.
- Common in historical or literary contexts to describe enemies or duplicitous allies.
Common Misconceptions
- Not just 'not honest'—it's deliberate betrayal.
- Can describe minor lapses in loyalty in everyday speech.
- Often confused with 'treacherous' but perfidious emphasizes breach of trust.
- Usually reserved for persons in positions of trust or authority.
- Noun form is perfidy; 'perfidious' is the adjective.
Thinking Differences
English speakers tend to reserve perfidious for strong moral condemnations or literary/historical contexts; learners might confuse it with merely dishonest or treacherous, missing the explicit breach of a trust bond.
Learning Tips
- Remember the strong negative tone.
- Pair with noun phrases: perfidious ally, perfidious scheme.
- Note the etymology: through faith, trust the idea.
- Differentiate from dishonest or treacherous in everyday use.
- Practice with political or literary sentences to sound natural.
- Watch for context cues: historical, moral, or dramatic.
5-Step Learning Method - Learn English in English
Step 1: Meaning
What is the meaning of the word 'perfidious'?
A.Loyal
B.Generous
C.Honest
D.Deceitful
Step 2: Usage
In which sentence is the word 'perfidious' used correctly?
A.She was known for her loyal and perfidious nature.
B.He always kept his promises without any perfidious intentions.
C.The generous donation was seen as perfidious by the recipient.
D.His perfidious actions were revealed by the evidence.
Step 3: Similar Words
Which word is a synonym of 'perfidious'?
A.Faithful
B.Disloyal
C.Honest
D.Altruistic
Step 4: Opposite Words
Which word is an antonym of 'perfidious'?
A.Deceitful
B.Loyal
C.Treacherous
D.Dishonest
Step 5: Mastery
In what real-life context would someone be described as 'perfidious'?
A.A doctor who shows immense care and honesty towards patients
B.A teacher who always keeps promises to students
C.A friend who betrays secrets and lies to others
D.A charity worker who selflessly helps those in need
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