know better

idiom

1
: to be smart or sensible enough not to do something
You walked home alone? Don't you know better (than that)?
She'll know better than to trust them again.
There's no excuse for his behavior. He's old enough to know better.
Don't blame him. He's just a child and he doesn't know (any) better.
2
: to know or understand the truth about something
She tried to tell me that it wasn't her fault, but I know better.
3
: to know or understand more than other people
You can't tell him what to do. He always thinks that he knows better.

Examples of know better in a Sentence

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These aren’t innocent mistakes — people know better and do it anyway. U T Readers, San Diego Union-Tribune, 30 June 2025 The cleaning aisles are full of what companies consider the latest and greatest, but professional cleaners know better than anyone what products get the job done. Quincy Bulin, Southern Living, 30 June 2025 Few know better than a perfumer that inspiration can come from anywhere. Noor Lobad, Footwear News, 27 June 2025 After all, Southerners know better than to show up empty-handed! Abigail Wilt, Southern Living, 9 June 2025 See All Example Sentences for know better

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Cite this Entry

“Know better.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/know%20better. Accessed 10 Jul. 2025.

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