lest

American  

[lest] / lɛst /

conjunction

1. for fear that; so that (one) should not (used negatively to introduce a clause expressive of an action or occurrence requiring caution).

   He kept his notes by his side lest faulty memory lead him astray.

2. that (used after words expressing fear, danger, etc.).

   There was danger lest the plan become known.

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idioms

1. lest we forget. lest we forget.

lest British  

/ lɛst /

conjunction

1. so as to prevent any possibility that

   he fled the country lest he be captured and imprisoned

2. (after verbs or phrases expressing fear, worry, anxiety, etc) for fear that; in case

   he was alarmed lest she should find out

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Etymology

Origin of lest

First recorded before 1000; Middle English leste, contraction of the lesse the, thi les the; late Old English the lǣste, earlier thȳ lǣs the, literally, “whereby less that” ( thȳ instrumental case of the demonstrative and relative pronoun, lǣs less, the conjunction)

Example Sentences

They cannot offer on-the-job training in the majors, lest their team find itself at a competitive disadvantage.

From Los Angeles Times

Chen agrees to help only on a pro bono basis—lest he himself draw unwanted attention: “You cannot be too careful nowadays,” a friendly citizen warns.

From The Wall Street Journal

I quickly ran my hands over my head to smooth down my hair from the center, lest she start commenting on the size of my ears.

From Literature

I kept my chatting to a minimum for the rest of that day, lest I drove my aunt crazy with conversation until she marched me back to the orphan asylum.

From Literature

My aunt was a stickler for staying in character lest we were overheard, even when the only creatures nearby that could possibly do any overhearing were the skeletons at the back of the room and a few stray mice.

From Literature