Thought I was dreaming vs Unbelievable

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

Thought I was dreaming

InformalBeyond 10,000 (less common)

Unbelievable

Top 1,000 (very common)
Most formal: UnbelievableMost common: Unbelievable
 Thought I was dreamingUnbelievable
Pronunciation🇬🇧 //θɔːt aɪ wəz ˈdriːmɪŋ//🇺🇸 //θɔt aɪ wəz ˈdrimɪŋ//🇬🇧 //ʌn.bɪˈliː.və.bəl//🇺🇸 //ʌn.bɪˈlivə.bəl//
MeaningAn expression used when something seems unbelievable or too good to be true.Not able to be believed; hard to accept as true.
ExampleWhen I saw the surprise party, I thought I was dreaming.His story about climbing Everest without oxygen was simply unbelievable.
RegisterInformalNeutral
How commonBeyond 10,000 (less common)Top 1,000 (very common)
Collocationsthink I'm dreaming, feel like I'm dreaming, amazing experience, unbelievable newsunbelievable story, unbelievable situation, unbelievable coincidence, unbelievable talent, unbelievable prices
Antonyms-credible, believable, plausible
Common mistakesConfusing with 'I thought I was dreaming'., Using in overly serious contexts., Misplacing the phrase within sentences.Confused with 'incredible' - both mean similar things but can have different connotations., Used too casually in serious contexts., Often mispronounced by stressing the wrong syllable.
Usage notesCommonly used in casual conversation, often to express surprise or disbelief. Not suitable for formal writing.Used to express astonishment or disbelief. It can be positive or negative depending on context (e.g., an unbelievable achievement vs. an unbelievable lie).

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Thought I was dreaming
Unbelievable

Frequently asked questions: Thought I was dreaming vs Unbelievable

What's the difference between Thought I was dreaming and Unbelievable?

Thought I was dreaming: An expression used when something seems unbelievable or too good to be true. Unbelievable: Not able to be believed; hard to accept as true.

Which is more formal: Thought I was dreaming and Unbelievable?

Unbelievable is the most formal of these.

Which is more common: Thought I was dreaming and Unbelievable?

Unbelievable is the most common in everyday English.

Can you show an example of each?

Thought I was dreaming: When I saw the surprise party, I thought I was dreaming. Unbelievable: His story about climbing Everest without oxygen was simply unbelievable.

Can I use Thought I was dreaming and Unbelievable interchangeably?

Not always. Thought I was dreaming and Unbelievable 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.