Doubt vs Suspect

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

Doubt

Top 1,000 (very common)B1noun

Suspect

Top 2,000 (common)B2verb
Most common: Doubt
 DoubtSuspect
Pronunciation🇬🇧 //daʊt//🇺🇸 //daʊt//🇬🇧 /["/səˈspekt/","/səˈspekts/","/səˈspektɪd/","/səˈspektɪŋ/"]/🇺🇸 /["/səˈspekt/","/səˈspekts/","/səˈspektɪd/","/səˈspektɪŋ/"]/
MeaningA feeling of not being sure about something.to think someone might be guilty or bad
ExampleHe expressed doubt about the accuracy of the report.The detective began to suspect that the alibi was fabricated.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelB1B2
Part of speechnounverb
Collocationsexpress doubt, have doubt, cast doubt, doubt someone's intentionsstrongly, rather, rightly, begin to, have reason to, have reasons to, be widely suspected, rightly, wrongly, of, have grounds for suspecting somebody/​something, have grounds to suspect somebody/​something, have reason to suspect somebody/​something
Antonymscertainty, confidence, belieftrust, believe, assure
Common mistakesConfused with 'suspicion' - 'doubt' refers to uncertainty, not mistrust., Using 'doubt' in affirmative sentences instead of negatives., Misunderstanding the difference between 'doubt' and 'question' as they aren't always interchangeable.Confused with 'suspected' - remember to use 'suspect' for present tense., Using 'suspect' without an object - always have something or someone you suspect., Mispronouncing it as 'suspect' like the noun form, when it is used as a verb.
Usage notesUsed when uncertain or unsure. Common in both spoken and written contexts. Avoid in very formal settings.Used when you have a feeling that someone is responsible for something negative. Not typically used for casual conversation unless referring to criminals. In formal contexts, it may require clarification.

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Doubt
Suspect

Frequently asked questions: Doubt vs Suspect

What's the difference between Doubt and Suspect?

Doubt: A feeling of not being sure about something. Suspect: to think someone might be guilty or bad

Which is more common: Doubt and Suspect?

Doubt is the most common in everyday English.

Which is more advanced: Doubt and Suspect?

Suspect is the highest level, at B2, on the CEFR scale.

Are Doubt and Suspect the same CEFR level?

Doubt: B1, Suspect: B2 on the CEFR scale.

What part of speech are Doubt and Suspect?

Doubt: noun, Suspect: verb.

Can you show an example of each?

Doubt: He expressed doubt about the accuracy of the report. Suspect: The detective began to suspect that the alibi was fabricated.

Can I use Doubt and Suspect interchangeably?

Not always. Doubt and Suspect 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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