Synonyms

no-no

American

[noh-noh] / ˈnoʊˌnoʊ /

noun

Informal.

plural

no-nos, no-no's

anything that is forbidden or not advisable, as because of being improper or unsafe.

If you want to lose weight, rich desserts are a no-no.

Etymology

Origin of no-no

1940–45, reduplication of no ¹

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The biggest no-no: Uploading documents with personal information into a publicly available AI tool.

From MarketWatch

That was a polar bear no-no, but they didn’t have a choice.

From Literature

“Natural light is the best. I can’t do a dark house. The no-no of no-nos is bad floor plan and flow, and not enough natural light.”

From MarketWatch

“The thing not to do? Don’t be insipid. A little jack lantern on the table — that’s not much of a Halloween gesture. I think you have to sort of go all out,” Stewart told Vogue last year when asked about her biggest Halloween no-no.

From Salon

Telling shoppers their goods are only worth a fraction of what they originally paid for them is also a no-no for brands.

From The Wall Street Journal

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023