therein lies the rub
Proposed by a contributor, not yet supported by evidence.
Meaning · English
A problem or difficulty exists in a particular situation
Nghĩa · Tiếng Việt
Vấn đề hoặc khó khăn nằm trong tình huống cụ thể
Machine-translated — suggest a fix
Literally: a problem lies in that
Where it’s used:
Used
Widespread English
Examples
I'd love to travel, but therein lies the rub: I don't have enough money
AI-drafted example auto-approved by rule (illustrative, not a corpus attestation)
Sources & notes
Listed in Wiktionary’s “English idioms” category (retrieved 2026-07-29); definition pending editorial review. Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-31; pending editor spot-check.
Common questions
What does “therein lies the rub” mean?
A problem or difficulty exists in a particular situation Literally: a problem lies in that
Is “therein lies the rub” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.