Fake friends are the kind of people who smile in your face but talk behind your back—and luckily, the English language has plenty of idioms to describe them.
In this article, we’ll explore 46 idioms that help you recognize, understand, and talk about fake friendships in a more expressive and memorable way.
Whether you’ve dealt with a backstabber, a two-faced liar, or someone who vanished when you needed them most, these idioms will give you the words to call them out—without having to say it directly.
What is an Idiom for Fake Friends?
An idiom for fake friends is a figurative expression used to describe people who pretend to be your friend while secretly working against you, abandoning you, or using you for their own benefit.
These idioms add depth and personality to everyday language, letting us talk about betrayal, dishonesty, and shallow relationships with wit and impact.
Let’s take a look at each idiom, break down its meaning, and see it in action.
Idioms About Fake Friends
1. A Snake in the Grass
Meaning: Someone who pretends to be friendly but is actually dangerous or deceitful.
In a Sentence: I thought she was on my side, but she turned out to be a snake in the grass, spreading rumors behind my back.
2. Two-Faced
Meaning: Someone who acts nice to your face but says bad things about you when you’re not around.
In a Sentence: He seemed supportive in person, but his texts revealed just how two-faced he really was.
3. Stab in the Back
Meaning: A betrayal by someone you trusted.
In a Sentence: I helped him get that job, and then he stabbed me in the back by stealing my clients.
4. Fair-Weather Friend
Meaning: A friend who is only around when things are going well and disappears during hard times.
In a Sentence: When I lost my job, all the fair-weather friends vanished, and only the real ones stuck by me.
5. Throw Under the Bus
Meaning: To betray someone for personal gain or to avoid blame.
In a Sentence: Instead of taking responsibility, she threw me under the bus in front of the entire team.
6. Wolf in Sheep’s Clothing
Meaning: Someone who appears harmless but is actually dangerous or deceitful.
In a Sentence: He came off as sweet and innocent, but he was a wolf in sheep’s clothing all along.
7. Talk Behind Your Back
Meaning: To say negative things about someone without them knowing.
In a Sentence: It hurt to find out they were talking behind my back after pretending to be supportive for weeks.
8. Blow Hot and Cold
Meaning: To be inconsistent in behavior or feelings, often friendly one moment and distant the next.
In a Sentence: I never knew where I stood with her—she was always blowing hot and cold.
9. Show True Colors
Meaning: To reveal one’s real personality, often when it’s unpleasant.
In a Sentence: When the crisis hit, she showed her true colors and abandoned everyone but herself.
10. Butter Wouldn’t Melt in Their Mouth
Meaning: Someone who appears innocent or sweet but is actually dishonest or manipulative.
In a Sentence: She acted like butter wouldn’t melt in her mouth, but she had no problem lying to get ahead.
11. Keep Your Friends Close and Your Enemies Closer
Meaning: Be cautious around those who might betray you, even if they seem like friends.
In a Sentence: I kept her in the group because I know she can’t be trusted—better to keep your enemies closer.
12. Backhanded Compliment
Meaning: A statement that seems like praise but is actually an insult.
In a Sentence: When she said, “You’re so brave to wear that,” I knew it was a backhanded compliment.
13. Throw Shade
Meaning: To make a subtle or indirect insult.
In a Sentence: She kept throwing shade during dinner with little comments meant to embarrass me.
14. Lip Service
Meaning: Saying something supportive without actually meaning it or taking action.
In a Sentence: He gave me lip service about being there for me, but he ghosted when I really needed help.
15. Blow Smoke
Meaning: To say insincere or deceptive things, often to gain favor.
In a Sentence: He was just blowing smoke, telling everyone how much he respected me while secretly taking credit for my work.
16. False Friend
Meaning: Someone who acts like a friend but behaves more like an enemy.
In a Sentence: She’s a classic false friend—quick to smile, quicker to betray.
17. Kiss Up
Meaning: To flatter someone insincerely, usually for personal gain.
In a Sentence: He only acts nice when he wants something—he’s always kissing up to the boss.
18. Cold Shoulder
Meaning: To intentionally ignore someone or treat them with indifference.
In a Sentence: After I stopped helping him cheat on tests, he gave me the cold shoulder like we’d never been friends.
19. Bad-Mouth
Meaning: To criticize or speak negatively about someone behind their back.
In a Sentence: I heard she was bad-mouthing me at the party after asking for my help the day before.
20. Break Trust
Meaning: To damage or destroy the confidence someone had in you.
In a Sentence: When she shared my secret, she broke my trust, and I couldn’t look at her the same way again.
21. Fake It Till You Make It
Meaning: Pretending to be something you’re not—can refer to insincerity in friendships.
In a Sentence: He wasn’t interested in being my friend—he was just faking it till he made it with the popular crowd.
22. Smile in Your Face, Stab You in the Back
Meaning: To act friendly while planning to betray.
In a Sentence: She smiled in my face and stabbed me in the back with a single email to my manager.
23. Act Like a Saint
Meaning: Pretending to be morally perfect while hiding dishonest behavior.
In a Sentence: He acted like a saint at church, but everyone knew how fake he was behind closed doors.
24. Pull the Wool Over Someone’s Eyes
Meaning: To deceive or trick someone.
In a Sentence: She pulled the wool over everyone’s eyes by pretending to support the project while secretly sabotaging it.
25. Hit Below the Belt
Meaning: To say or do something unfair or cruel, especially to someone close.
In a Sentence: I thought we were friends, but that comment about my family really hit below the belt.
26. Ride Your Coattails
Meaning: To benefit from someone else’s success without doing the work.
In a Sentence: He didn’t contribute to the group project, but he rode my coattails all the way to an A.
27. Burn Bridges
Meaning: To ruin a relationship permanently.
In a Sentence: After gossiping about everyone, she burned so many bridges that nobody trusts her anymore.
28. Run Hot and Cold
Meaning: To act inconsistently—friendly at times and distant at others.
In a Sentence: He ran hot and cold depending on who was watching, which made me question our friendship.
29. Wolf Pack Mentality
Meaning: When people follow the group and turn against someone, often unfairly.
In a Sentence: As soon as the gossip started, the fake friends showed their wolf pack mentality and ganged up on her.
30. Play Both Sides
Meaning: To pretend to support two opposing people or groups for personal advantage.
In a Sentence: She played both sides, pretending to be my friend while feeding information to my rival.
31. Fair-Weather Loyalty
Meaning: Loyalty that only lasts while things are easy or beneficial.
In a Sentence: His fair-weather loyalty vanished the moment I stopped being useful to him.
32. Step on Toes
Meaning: To offend or upset someone, especially when overstepping boundaries.
In a Sentence: He stepped on my toes by taking credit for my idea and acting like it was teamwork.
33. Play the Victim
Meaning: To pretend to be innocent or wronged to gain sympathy.
In a Sentence: She played the victim after starting all the drama, making me look like the bad guy.
34. Dig the Knife Deeper
Meaning: To make a betrayal or insult worse by continuing or adding more pain.
In a Sentence: He already hurt me with his lies, but gossiping afterward really dug the knife deeper.
35. Put on a Front
Meaning: To act a certain way to hide your true feelings or intentions.
In a Sentence: She put on a friendly front at school but mocked everyone once they walked away.
36. A Back Pocket Friend
Meaning: Someone who only reaches out when they need something.
In a Sentence: I realized I was just a back pocket friend when he only called during emergencies.
37. Paint a Pretty Picture
Meaning: To make things look better than they are, hiding the truth.
In a Sentence: She painted a pretty picture of our friendship, but deep down, it was one-sided and fake.
38. Build You Up to Tear You Down
Meaning: To compliment or support someone only to betray or criticize them later.
In a Sentence: He built me up with praise and then tore me down in front of the whole class.
39. Be on a Short Leash
Meaning: Being overly controlled or manipulated, often by a toxic friend.
In a Sentence: She acted like my friend but kept me on a short leash, dictating everything I did.
40. Fake It on Social Media
Meaning: Pretending to have close friendships online that don’t exist in real life.
In a Sentence: We hadn’t spoken in months, but she tagged me in photos to fake it on social media.
41. Silent Treatment
Meaning: Deliberately ignoring someone to punish or manipulate them.
In a Sentence: After I called her out, she gave me the silent treatment for a week like a child.
42. Look Down Your Nose
Meaning: To act superior or judgmental toward others.
In a Sentence: She looked down her nose at me once I stopped being useful, pretending I didn’t exist.
43. Smile Through Gritted Teeth
Meaning: To pretend to be happy or friendly when you’re actually angry or annoyed.
In a Sentence: He smiled through gritted teeth when I got promoted—jealousy masked as support.
44. Blow Things Out of Proportion
Meaning: To exaggerate minor problems, often for attention or manipulation.
In a Sentence: Fake friends blow things out of proportion to create drama and play the victim.
45. Be a Chameleon
Meaning: To change your behavior to fit in with different people, often insincerely.
In a Sentence: He was a social chameleon—friendly in public, shady in private, and fake everywhere else.
46. Jump Ship
Meaning: To abandon someone or something, especially when things get hard.
In a Sentence: As soon as I needed help, my so-called friend jumped ship without a second thought.
Quizzes About The Idioms in This Article
Quiz 1: Snake in the Grass
What does the idiom “A snake in the grass” mean?
a) A quiet and peaceful person
b) A sneaky or deceitful person pretending to be kind
c) A hardworking and loyal friend
d) A pet lover
Quiz 2: Fair-Weather Friend
When someone is a “fair-weather friend,” how do they behave?
a) They stick around in bad times
b) They disappear when you need them
c) They enjoy the outdoors
d) They only talk about the weather
Quiz 3: Throw Someone Under the Bus
What does “throw under the bus” imply?
a) Help someone with a big task
b) Betray someone to protect yourself
c) Push someone into traffic
d) Let someone drive a bus
Quiz 4: Show True Colors
What happens when someone “shows their true colors”?
a) They dye their hair
b) They finally act kindly
c) They reveal their real personality
d) They get nervous
Quiz 5: Silent Treatment
What is the “silent treatment”?
a) Singing softly
b) Not responding to texts
c) Ignoring someone intentionally
d) Whispering secrets
Quiz 6: Play the Victim
If someone “plays the victim,” what are they doing?
a) Helping others
b) Admitting fault
c) Pretending to be wronged
d) Solving problems
Quiz 7: Blow Smoke
What does it mean to “blow smoke”?
a) Light a fire
b) Cook food
c) Say things that aren’t sincere
d) Get angry
Quiz 8: Keep Your Friends Close and Enemies Closer
What does this idiom suggest?
a) Stay away from everyone
b) Always be alone
c) Watch your enemies by pretending to be friendly
d) Make everyone your friend
Quiz 9: Jump Ship
What does “jump ship” mean in the context of friendships?
a) Go on vacation
b) Leave when times are tough
c) Start a cruise business
d) Sail away with a friend
Quiz 10: Build You Up to Tear You Down
What does this phrase describe?
a) A kind-hearted friend
b) Someone who always compliments
c) Someone who supports then betrays
d) Someone who fixes broken things
Answers:
- b
- b
- b
- c
- c
- c
- c
- c
- b
- c
Conclusion
Fake friends can be hard to spot—but idioms help us express the truth in ways that feel powerful, precise, and even poetic. Whether you’ve been stabbed in the back or given the cold shoulder, these expressions give voice to betrayal and let you call out fakeness without saying it directly.
Keep these idioms in your emotional toolkit—you never know when you’ll need the right words to describe someone smiling in your face while hiding a knife behind their back.