Coincidence vs Fluke

When to use each in English, with meaning, register, and examples.

Coincidence

Top 2,000 (common)B2noun

Fluke

Top 5,000 (fairly common)
Most common: Coincidence
 CoincidenceFluke
Pronunciation🇬🇧 /["/kəʊˈɪnsɪdəns/"]/🇺🇸 /["/kəʊˈɪnsɪdəns/"]/🇬🇧 //fluːk//🇺🇸 //fluːk//
MeaningWhen two things happen at the same time by chance.A lucky chance or accident.
ExampleIt was just a coincidence that we ran into each other at the café.Winning the lottery was just a complete fluke.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 5,000 (fairly common)
CEFR levelB2-
Part of speechnoun
Collocationscomplete, pure, sheer, series, set, string, happen, by (a) coincidencelucky fluke, total fluke, fluke event
Antonymsintention, design-
Common mistakesConfusing 'coincidence' with 'coincidental' — the latter is an adjective., Using 'coincidence' when describing causal relationships instead of chance., Overusing in formal writing; it's better in casual conversation.Confusing with 'flukes' in anatomy., Using as a verb instead of a noun., Mixing up with 'lucky' or 'chance' in contexts.
Usage notesUse 'coincidence' when referring to events that happen together unexpectedly. Avoid using it in formal scientific contexts, where 'correlation' might be more appropriate.Often used informally to describe unexpected good fortune. Not suitable for formal writing.

See it in real clips

Coincidence
Fluke

Frequently asked questions: Coincidence vs Fluke

What's the difference between Coincidence and Fluke?

Coincidence: When two things happen at the same time by chance. Fluke: A lucky chance or accident.

Which is more common: Coincidence and Fluke?

Coincidence is the most common in everyday English.

Can you show an example of each?

Coincidence: It was just a coincidence that we ran into each other at the café. Fluke: Winning the lottery was just a complete fluke.

Can I use Coincidence and Fluke interchangeably?

Not always. Coincidence and Fluke are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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