1
[ adverb ] for fear that

Examples

"she tiptoed lest her mother should hear her"

Used in print

(W. E. B. DuBois, Worlds of Color....)

She soared over the new pastor like an avenging angel lest he stray from the path and not know all the truth and gossip of which she was chief repository .

(Guy Endore, Voltaire! Voltaire!...)

He trembled lest his piece should fail .

his fear lest in this closed hall he should suddenly itch to relieve_himself .

2
[ conjunction ] coordinating conjunction, in order that not
3
[ adverb ] that (after verbs explicitly expressing fear etc.)

Examples

"he worried lest he should be late"

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