unacceptable

adjective

un·​ac·​cept·​able ˌən-ik-ˈsep-tə-bəl 

-ak-

: not acceptable : not pleasing or welcome

unacceptability

ˌən-ik-ˌsep-tə-ˈbi-lə-tē 

noun

unacceptably

ˌən-ik-ˈsep-tə-blē 

adverb

Synonyms of unacceptable

• wrong
• poor
• lame
• bad
• horrible
• terrible
• deficient
• awful
• unsatisfactory
• flawed
• disastrous
• pathetic

Examples of unacceptable in a Sentence

a word that is unacceptable in formal English

Some of her ideas were unacceptable to other people.

Recent Examples on the Web

Kip Dellinger Santa Monica The type of play by the Chargers on Sunday was completely unacceptable, lackluster and disappointing for a team with Super Bowl aspirations. — Los Angeles Times, 19 Sep. 2026

After monitoring the situation, park managers found the bear unusually difficult to scare away and said its escalating proximity to humans posed a safety risk that was deemed unacceptable, according to the national park. — Megan Fahrney, ABC News, 16 Sep. 2026

The Anti-Defamation League called Macklemore's comments unacceptable, and the Israeli American Council circulated a petition seeking his removal from the rest of the tour. — Paula Wethington, CBS News, 15 Sep. 2026

Predominantly African American communities should not be expected to tolerate conditions that government has concluded are unacceptable in downtown Baltimore. — Lawrence Bell, Baltimore Sun, 15 Sep. 2026

Word History

First Known Use

15th century, in the meaning defined above

Rhymes for unacceptable

• acceptable
• perceptible
• susceptible
• imperceptible

Kids Definition

unacceptable

adjective

un·​ac·​cept·​able ˌən-ik-ˈsep-tə-bəl 

-ak-

: not acceptable : not pleasing or welcome

unacceptably

-blē 

adverb