Can 'can of worms' be used in formal writing?

It is informal. In formal contexts, alternatives like 'complex issue', 'multifaceted problem', or 'Pandora's box' are preferred.

Is it always negative?

Yes, it exclusively describes a problematic, troublesome situation with negative consequences.

What's the difference between 'can of worms' and 'Pandora's box'?

They are very close synonyms. 'Pandora's box' can sound slightly more literary or dramatic, while 'can of worms' is more everyday and conversational.

Can you 'close' a can of worms?

Not idiomatically. The idiom focuses on the act of opening/revealing. Once opened, the problems exist. People might say 'try to close that can of worms' non-idiomatically, meaning to resolve the many problems.

How do you pronounce “can of worms”?

Can of worms: in British English it is pronounced /ˌkæn əv ˈwɜːmz/, and in American English it is pronounced /ˌkæn əv ˈwɝːmz/. Tap the audio buttons above to hear it.

can of worms: meaning, definition, pronunciation and examples

UK/ˌkæn əv ˈwɜːmz/US/ˌkæn əv ˈwɝːmz/

Informal, Figurative

My Flashcards

Quick answer

What does “can of worms” mean?

A complex, problematic situation that, once begun, leads to many unforeseen difficulties and complications.

Audio

Pronunciation

Definition

Meaning and Definition

A complex, problematic situation that, once begun, leads to many unforeseen difficulties and complications.

A source of unforeseen and uncontrollable problems; an issue that, when addressed, reveals or creates many other related problems.

Dialectal Variation

British vs American Usage

Differences

No significant difference in meaning or usage. Both varieties use it identically.

Connotations

Strongly negative, implying trouble, complexity, and regret for having started the inquiry.

Frequency

Equally common and well-understood in both dialects.

Grammar

How to Use “can of worms” in a Sentence

open + a + can of wormsbe + a + can of wormsturn into + a + can of worms

Vocabulary

Collocations

strong

openopen upuncoverreveal

medium

a reala wholeanotherthat

weak

investigatediscussdeal withhandle

Examples

Examples of “can of worms” in a Sentence

verb

British English

The inquiry really opened a can of worms for the council.

American English

Bringing up the zoning laws opened a whole can of worms.

adjective

British English

(Non-standard, rare) We're facing a real can-of-worms scenario with this legacy software.

American English

(Non-standard, rare) It was a classic can-of-worms situation after the merger.

Usage

Meaning in Context

Business

Used when a financial audit reveals systemic fraud.

Academic

Describing a research question that branches into numerous unresolved ethical debates.

Everyday

Used when asking about family history uncovers long-held secrets and conflicts.

Technical

Rare; could describe a software bug that reveals many other underlying flaws in the codebase.

Vocabulary

Synonyms of “can of worms”

Strong

Pandora's box quagmire hornet's nest

Neutral

complicated issuemessy situationtangled problem

Weak

difficulty complication challenge

Vocabulary

Antonyms of “can of worms”

simple solutionstraightforward matterclear-cut issue

Watch out

Common Mistakes When Using “can of worms”

Using it as an adjective (e.g., 'a can-of-worms problem' – this is rare and non-standard). Forgetting the article 'a' (e.g., 'It is can of worms').

FAQ

Frequently Asked Questions

: It is informal. In formal contexts, alternatives like 'complex issue', 'multifaceted problem', or 'Pandora's box' are preferred.
: Yes, it exclusively describes a problematic, troublesome situation with negative consequences.
: They are very close synonyms. 'Pandora's box' can sound slightly more literary or dramatic, while 'can of worms' is more everyday and conversational.
: Not idiomatically. The idiom focuses on the act of opening/revealing. Once opened, the problems exist. People might say 'try to close that can of worms' non-idiomatically, meaning to resolve the many problems.
: A complex, problematic situation that, once begun, leads to many unforeseen difficulties and complications.
: Can of worms: in British English it is pronounced /ˌkæn əv ˈwɜːmz/, and in American English it is pronounced /ˌkæn əv ˈwɝːmz/. Tap the audio buttons above to hear it.

Phrases

Idioms & Phrases

“Pandora's box”
“open a hornet's nest”

Learning

Memory Aids

Mnemonic

Imagine literally opening a tin full of worms – they spill out uncontrollably, creating a huge, messy problem. The idiom captures that exact feeling of regret and chaos.

Conceptual Metaphor

PROBLEMS ARE PHYSICAL ENTITIES CONTAINED; INVESTIGATION IS OPENING A CONTAINER.

Practice

Quiz

Fill in the gap

The journalist didn't realise her question about the mayor's early career would such a can of worms.

Multiple Choice

What is the primary implication of describing something as 'a can of worms'?