unacceptable

British  

/ ˌʌnəkˈsɛptəbəl /

adjective

1. not satisfactory; inadequate

   the standard was wholly unacceptable

2. intolerable

   hitting children is unacceptable

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Explanation

Something unacceptable is not okay — it's objectionable or displeasing. Hey, are you yelling in the library? That's unacceptable! If a student's behavior is unacceptable, she may get detention or be sent to the principal's office. And if a restaurant patron's meal is unacceptable, he has every right to ask his server for something else. The adjective unacceptable adds the "not" prefix un- to acceptable, "suitable, adequate, or pleasing." We can trace the roots back to the Latin acceptare, "take or receive willingly."

Example Sentences

"The other children, despite us having this amazing and innovative therapy, we have had to send them home essentially to die like Teddy. This is unacceptable to us," he said.

From BBC • Jun. 2, 2026

A planning officer told the council there were 19 letters of support and the development would not result in any unacceptable impact on the character or appearance of the area.

From BBC • Jun. 1, 2026

Democratic state Governor Mikie Sherrill added: "We've seen the risk to public safety rising outside of Delaney Hall, it has grown unsafe, and that's completely unacceptable."

From Barron's • May 29, 2026

Its Prime Minister Feleti Teo has made clear that he believes "opening, subsidising and exporting fossil fuels is immoral and unacceptable".

From Barron's • May 28, 2026

“Tell her it’s unacceptable for her to spar.”

From "Throne of Glass" by Sarah J. Maas

Related Words

• distasteful
• improper
• inadmissible
• objectionable
• offensive
• repugnant
• undesirable
• unsatisfactory