# unacceptable

/ˌənækˈsɛptəbəɫ/ (US) · /ʌnɐksˈɛptəbəl/ (UK)

Source: https://englishreference.com/word/unacceptable
Updated: 2026-06-20

## Senses

### 1. not good enough

adjective · CEFR B2

not good enough to be allowed or accepted by others.

For teachers: failing to meet a required standard or social expectation; deemed intolerable or unsatisfactory.

- The long delays at the airport were completely unacceptable to the passengers.
- The committee found the proposed safety measures to be wholly unacceptable, citing numerous gaps in the emergency evacuation protocols.

### 2. linguistically incorrect

adjective · CEFR C1 · Academic · Technical

describing a word or sentence that does not follow the rules of a language.

For teachers: describing a linguistic form that does not conform to the rules of a specific grammar or the norms of a speech community.

- In English, saying 'he go' is considered unacceptable in formal writing.
- The generative model rejected the string as unacceptable because it violated the core principles of phrase structure within that specific dialect.

Usage: In linguistics, this is often marked with an asterisk (*) before the sentence.

### 3. something rejected

noun · CEFR C2 · Formal

a person or thing that is not accepted by a group.

For teachers: an entity, person, or proposal that has been rejected or deemed unsuitable for inclusion.

- The social club was known for its harsh treatment of unacceptables.
- The archive was divided into two sections: those documents deemed worthy of preservation and the unacceptables destined for the shredder.

## Examples

- The manager told him that his rude behavior was unacceptable.
- The airline offered a small voucher as compensation, but the passengers found the offer completely unacceptable given the long delay.
- While minor errors are expected in a first draft, the sheer volume of factual inaccuracies in the final report was deemed unacceptable by the board of directors.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.