Uncertainty vs We have a reasonable doubt

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

Uncertainty

Top 1,000 (very common)B2noun

We have a reasonable doubt

FormalBeyond 10,000 (less common)
Most formal: We have a reasonable doubtMost common: Uncertainty
 UncertaintyWe have a reasonable doubt
Pronunciation🇬🇧 /["/ʌnˈsɜːtnti/"]/🇺🇸 /["/ʌnˈsɜːrtnti/"]/🇬🇧 //wiː hæv ə ˈriːzənəbl daʊt//🇺🇸 //wi hæv ə ˈrizənəbl daʊt//
MeaningNot being sure about something.We think something might not be true.
ExampleThe uncertainty about the future made it difficult for her to make long-term plans.The jury concluded there was a __we have a reasonable doubt__ about the defendant's guilt.
RegisterNeutralFormal
How commonTop 1,000 (very common)Beyond 10,000 (less common)
CEFR levelB2-
Part of speechnoun
Collocationsconsiderable, great, high, amount, degree, element, cause, create, generate, surround something, exist, remain, uncertainty about, uncertainty as to, uncertainty in, an area of uncertainty, an atmosphere of uncertainty, a climate of uncertainty, considerable, great, high, amount, degree, element, cause, create, generate, surround something, exist, remain, uncertainty about, uncertainty as to, uncertainty in, an area of uncertainty, an atmosphere of uncertainty, a climate of uncertaintybeyond reasonable doubt, establish reasonable doubt, raise reasonable doubt
Antonymscertainty, assurance, confidencecertainty, conviction, confidence, surety
Common mistakesConfusing 'uncertainty' with 'insecurity' which has different meanings., Using 'uncertainty' in situations that require more concrete terms., Not differentiating between 'uncertainty' as a state and the causes of that uncertainty.Confused with 'reasonable certainty'., Using it in everyday contexts outside the legal system., Misusing it to suggest complete disbelief.
Usage notesUse 'uncertainty' in formal discussions, such as scientific or academic contexts. Avoid it in casual conversations where simpler words like 'doubt' may be more appropriate.Used mainly in legal contexts to indicate uncertainty about a person's guilt. Not suitable for casual conversations.

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We have a reasonable doubt

Frequently asked questions: Uncertainty vs We have a reasonable doubt

What's the difference between Uncertainty and We have a reasonable doubt?

Uncertainty: Not being sure about something. We have a reasonable doubt: We think something might not be true.

Which is more formal: Uncertainty and We have a reasonable doubt?

We have a reasonable doubt is the most formal of these.

Which is more common: Uncertainty and We have a reasonable doubt?

Uncertainty is the most common in everyday English.

Can you show an example of each?

Uncertainty: The uncertainty about the future made it difficult for her to make long-term plans. We have a reasonable doubt: The jury concluded there was a __we have a reasonable doubt__ about the defendant's guilt.

Can I use Uncertainty and We have a reasonable doubt interchangeably?

Not always. Uncertainty and We have a reasonable doubt 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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