Meaning of lest

lest

Pronunciation: (lest), [key]
— conj.
  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.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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