Perfidious
/pərˈfɪdiəs/
adjectiveC2
Definition
Perfidious means not loyal or faithful to someone who trusts you. It describes a person or action that breaks trust by being dishonest or betraying others. This word is often used in serious situations where trust is very important.
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See It in Action
Showing betrayal or treachery by breaking trust
- •The perfidious servant stole from his master and lied about it.
- •She was shocked by her perfidious friend's betrayal.
- •Perfidious actions can destroy important relationships.
Make It Stick
- ✓Think of "perfidious" like "untrustworthy" (A2 word), but much stronger and more serious—someone who breaks promises in a very bad way
- ✓Picture a friend who secretly tells your secrets to others, causing harm and sadness
- ✓It's the feeling of deep disappointment when someone you trusted acts against you
- ✓Sounds like "per-FID-ee-us" → imagine a "per-fid" (perfectly bad) person who tricks friends and breaks their trust
- ✓Remember stories or movies where a character betrays a friend or country, like a spy who works for the enemy
- ✓NOT like "mistake" (accidental), "perfidious" means a planned and harmful betrayal
- ✓NOT like "unfriendly" (just not nice), "perfidious" means actively betraying trust and loyalty
Try Other Words
- •Treacherous: showing betrayal or danger (Use when you want to emphasize danger or harm caused by betrayal)
- •Disloyal: not loyal or faithful (Use when focusing on lack of loyalty in friendships or groups)
- •Faithless: not keeping promises or trust (Use in formal or literary contexts)
Unboxing
- •Word parts: prefix "per-" (through, completely) + root "fid" (trust, faith) + suffix "-ious" (adjective form)
- •Etymology: From Latin "perfidiosus," meaning "faithless, treacherous"
- •Historical development: Used since the 1400s in English to describe someone who breaks trust completely
- •Modern usage: Mostly used in formal, literary, or serious contexts to describe deep betrayal
Reflect & Connect
•Can a person be forgiven after being perfidious? What would need to happen?
•How does the feeling of betrayal affect relationships compared to simple mistakes or misunderstandings?
Fill in the blanks
1.A perfidious person often plans to ___ the trust others have in them.
2.When someone acts perfidious, it usually causes ___ and broken friendships.
3.Unlike a small lie, perfidious behavior is a ___ betrayal that hurts deeply.
4.The phrase "perfidious ally" means a friend who ___ you in a difficult time.
5.People who are perfidious often hide their true ___ until they betray you.
6.You would not describe a helpful and honest person as perfidious because they ___ loyalty.
7.In stories, a perfidious character often ___ the main hero by acting secretly against them.