LEST


Meaning of LEST in English

If you do something ~ something unpleasant should happen, you do it to try to prevent the unpleasant thing from happening. (FORMAL)

I was afraid to open the door ~ he should follow me...

And, ~ we forget, Einstein wrote his most influential papers while working as a clerk.

= in case

CONJ

Collins COBUILD.      Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) .