know it all
B2Informal, slightly pejorative
Definition
Meaning
A person who behaves as if they know everything and refuses to accept advice or information from others.
Someone who displays an irritating, overconfident, and often unwarranted certainty about their knowledge across various topics, typically dismissing others' input.
Linguistics
Semantic Notes
Primarily used as a compound noun. Carries a negative connotation of arrogance and insufferability. Not typically used as a self-description.
Dialectal Variation
British vs American Usage
Differences
Usage and meaning are identical. The spelling with hyphens ('know-it-all') is standard in both, though informal writing may omit hyphens.
Connotations
Equally pejorative in both varieties. Slightly more common in American English as a direct label.
Frequency
Moderately common in both. American English may have slightly more colloquial synonyms in frequent use (e.g., 'smart aleck').
Vocabulary
Collocations
Grammar
Valency Patterns
He is such a [know-it-all].Don't be a [know-it-all].She acted like a real [know-it-all] during the meeting.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “A little knowledge is a dangerous thing (related concept)”
- “Jack of all trades, master of none (contrasting concept)”
Usage
Context Usage
Business
"The new consultant is a bit of a know-it-all, which is frustrating the team."
Academic
Rare in formal writing; used in informal discussion about peers: "He has a know-it-all reputation in seminars."
Everyday
"My brother is such a know-it-all about football."
Technical
Not used in technical registers.
Examples
By Part of Speech
verb
British English
- N/A
American English
- N/A
adverb
British English
- N/A
American English
- N/A
adjective
British English
- He has a know-it-all attitude that puts people off.
- I can't stand her know-it-all tone.
American English
- His know-it-all demeanor is really annoying.
- She gave a know-it-all answer that was factually wrong.
Examples
By CEFR Level
- My classmate is a know-it-all.
- He acts like a know-it-all.
- Nobody likes a know-it-all who interrupts all the time.
- She can be a bit of a know-it-all about history.
- Despite his know-it-all facade, he was often mistaken about the details.
- The meeting was dominated by a couple of know-it-alls who wouldn't let others speak.
- His know-it-all pronouncements on topics outside his expertise eventually eroded his credibility.
- The panel discussion was marred by the know-it-all interventions of one particularly arrogant academic.
Learning
Memory Aids
Mnemonic
Imagine someone who says 'I KNOW IT ALL' before you even finish your sentence.
Conceptual Metaphor
KNOWLEDGE IS A POSSESSION (held exclusively and completely). ARGUMENT IS WAR (dismissing others' views).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not translate literally as 'знать это всё'. The phrase is an idiom.
- Avoid confusing with 'всезнайка', which is a close equivalent but more childish in tone.
- Do not use 'умник' as a direct translation—it is less specific.
Common Mistakes
- Using it as a verb (*'He know-it-alls everything').
- Spelling as 'know it all' without hyphens in formal writing.
- Using it in a positive context (*'She's a helpful know-it-all').
Practice
Quiz
In which context is 'know-it-all' LEAST likely to be used?
FAQ
Frequently Asked Questions
Yes, but with careful tone and established rapport. It remains mildly critical even when joking.
"Expert" or "enthusiast" are positive. "Walking encyclopedia" can be used humorously with less offence.
An expert has proven knowledge in a specific field. A know-it-all claims broad, often superficial knowledge and is defined by their arrogant attitude, not their actual expertise.
The standard spelling is 'know-it-all'. Variations like 'know it all' (open) are seen in very informal contexts but are not standard.
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