That's out of the question vs Unacceptable

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

That's out of the question

Top 5,000 (fairly common)

Unacceptable

FormalTop 3,000 (common)B2adjective
Most formal: UnacceptableMost common: Unacceptable
 That's out of the questionUnacceptable
Pronunciation🇬🇧 //ðæts aʊt əv ðə ˈkwɛsʧən//🇺🇸 //ðæts aʊt əv ðə ˈkwɛsʧən//🇬🇧 /["/ˌʌnəkˈseptəbl/"]/🇺🇸 /["/ˌʌnəkˈseptəbl/"]/
MeaningIt's impossible or not allowed.Not okay or not allowed.
ExampleAsking for a pay raise after just a month on the job? That's out of the question.Such behaviour is totally unacceptable in a civilized society.
RegisterNeutralFormal
How commonTop 5,000 (fairly common)Top 3,000 (common)
CEFR level-B2
Part of speechadjective
Collocationscompletely out of the question, quite out of the question, absolutely out of the questionbe, prove, seem, absolutely, completely, entirely, to
Antonyms-acceptable, agreeable, satisfactory
Common mistakesUsing it when discussing approved actions instead of refusals., Confusing it with 'that's not an option' and misusing it in more casual conversations.Confused with 'unacceptable' and 'unexceptable'., Used in casual contexts where simpler words like 'not okay' would fit better., Mispronounced, especially the 'un' part.
Usage notesUse this phrase in discussions when you want to refuse a suggestion or idea. It's appropriate in both formal and informal settings but should not be used in overly casual contexts.Use 'unacceptable' in formal situations, such as professional settings or written complaints. Avoid in casual conversations.

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That's out of the question

Frequently asked questions: That's out of the question vs Unacceptable

What's the difference between That's out of the question and Unacceptable?

That's out of the question: It's impossible or not allowed. Unacceptable: Not okay or not allowed.

Which is more formal: That's out of the question and Unacceptable?

Unacceptable is the most formal of these.

Which is more common: That's out of the question and Unacceptable?

Unacceptable is the most common in everyday English.

Can you show an example of each?

That's out of the question: Asking for a pay raise after just a month on the job? That's out of the question. Unacceptable: Such behaviour is totally unacceptable in a civilized society.

Can I use That's out of the question and Unacceptable interchangeably?

Not always. That's out of the question and Unacceptable 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.