infallible
gb/ɪnfˈæləbəl/ us/ɪnfˈæləbəl/
C1
English
Senses
0 senses
adjective
formal
C1
property
1
never making mistakes
If someone is infallible, they are always right.
Usage pattern:
[someone] is infallible
Common mistake:
Do not confuse with inevitable (certain to happen) or invincible (cannot be defeated).
Synonyms
unerring (More literary; emphasizes not making mistakes.)
|
always right (More informal and straightforward.)
Antonyms
fallible (Capable of making mistakes.)
|
mistaken (Wrong in a particular case.)
Collocations
seem infallible
|claim to be infallible
|think you are infallible
|consider [someone] infallible
|an infallible judge
|an infallible authority
|infallible logic
|infallible memory
|infallible instinct
|an infallible expert
Themes
communication
|opinions
|people
Examples
- She’s brilliant, but she isn’t infallible.
- He spoke as if his judgment were infallible.
- No human being is infallible, so we double-check our work.
Learner examples
- My teacher is not infallible.
- I am not infallible, so I check my answers.
adjective
formal
C1
property
2
certain to work every time
If something is infallible, it always works and never fails.
Usage pattern:
an infallible [method/way/test/sign]
Common mistake:
In everyday English this is often an exaggeration; speakers may mean “very reliable,” not literally perfect.
Synonyms
foolproof (Emphasizes that it is hard for people to use incorrectly.)
|
reliable (Weaker; means it usually works well, not perfectly.)
Antonyms
unreliable (Not dependable; may fail.)
|
fallible (Capable of error or failure.)
Collocations
an infallible method
|an infallible way
|an infallible test
|an infallible sign
|an infallible indicator
|an infallible cure
|an infallible system
|an infallible recipe
|infallible means
|an infallible solution
Themes
daily_life
|problem_solving
|products
Examples
- There’s no infallible way to predict the stock market.
- A smile isn’t an infallible sign that someone is happy.
- The app is helpful, but it’s not infallible.
Learner examples
- This test is not infallible.
- There is no infallible method.
adjective
formal
C2
property
3
religiously incapable of doctrinal error
In religion, infallible can mean “cannot be wrong about official beliefs.”
Usage pattern:
[religious authority/text] is infallible
Common mistake:
This sense is specialized; in general conversation, infallible usually just means “always right.”
Synonyms
authoritative (Not the same; means trusted or official, not necessarily incapable of error.)
Antonyms
fallible (Capable of error, including in teaching or judgment.)
Collocations
an infallible pope
|an infallible authority
|an infallible church
|an infallible scripture
|infallible teaching
|infallible doctrine
Themes
religion
|history
|politics
Examples
- Some believers treat the text as infallible.
- The debate centered on whether any human institution can be infallible.
- They rejected the idea of an infallible religious authority.
Grammar
Dictionary form
infallible
IPA
GB/ɪnfˈæləbəl/
US/ɪnfˈæləbəl/
Syllables & stress
in - fal - lible (3 syllables)
Stress on 2nd syllable (fal)
Word forms
Adjective
- Base: infallible
Word family
Core family
infallibility
noun C1
infallibly
adverb C1
Negative and opposite forms
fallible
adjective
fallibility
noun
Advanced or less common
fallacy
noun B2
fallacious
adjective
Expressions
no one is infallible.
1/nˈoʊ wˈʌn ˈɪz ɪnfˈæləbəl ‖/
fixed phrase
everyone can make mistakes
Everyone makes mistakes sometimes.
Examples
- I made a mistake, but no one is infallible.
- Try not to be too harsh—no one is infallible.
- He apologized and reminded the team that no one is infallible.
treat [someone] as infallible
1/tɹˈit sˈʌmwˌʌn ˈæz ɪnfˈæləbəl/
fixed phrase
assume someone is always right
To act like someone is always right.
Examples
- Don’t treat celebrities as infallible just because they’re famous.
- She treated her manager as infallible and never challenged bad decisions.
- The article warns against treating any leader as infallible.