: for fear that
often used after an expression denoting fear or apprehension
worried lest she should be late
hesitant to speak out lest he be fired

Word History


Middle English les the, leste, from Old English thȳ lǣs the, from thȳ (instrumental of thæt that) + lǣs + the, relative particle

First Known Use

before the 12th century, in the meaning defined above

Time Traveler
The first known use of lest was before the 12th century

Dictionary Entries Near lest

Cite this Entry

“Lest.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lest. Accessed 30 Sep. 2023.

Kids Definition


: for fear that
tied the dog lest it should escape

More from Merriam-Webster on lest

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