mightn't

contraction

ˈmī-tᵊnt How to pronounce mightn't (audio)
: might not

Word History

First Known Use

1781, in the meaning defined above

Time Traveler
The first known use of mightn't was in 1781

Dictionary Entries Near mightn't

might/may as well

mightn't

might/should have known

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Cite this Entry

“Mightn't.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mightn%27t. Accessed 21 Dec. 2024.

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Kids Definition

mightn't

ˈmīt-ᵊnt How to pronounce mightn't (audio)
: might not
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