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

He said his his team's performance in the defeat by Brighton was both "indefensible" and "unacceptable".

From BBC • Apr. 22, 2026

Lowri Mair Williams is facing a fitness to practice hearing over unacceptable conduct while girls' rugby lead at Llandovery College, Carmarthenshire.

From BBC • Apr. 21, 2026

The government said: "Any form of abuse against someone simply going about their day-to-day work is completely unacceptable."

From BBC • Apr. 20, 2026

“He was incredibly brave to come forward and to be a plaintiff ... To be targeted because he is pursuing his rights is unacceptable, but not surprising given what we’ve been seeing.”

From Los Angeles Times • Apr. 17, 2026

Schooled to believe that self-indulgence of any kind was morally unacceptable, Ellen was deeply ashamed of her dependency upon coffee.

From "Across Five Aprils" by Irene Hunt

Related Words

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