Let-alone Definition

conjuntion

(idiomatic, negative polarity item) Much less; to say nothing of; used after one negative clause to introduce another, usually broader and more important clause, whose negation is implied by the negation of the first.

He couldn't boil water, let alone prepare a dinner for eight.

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(idiomatic, positive polarity item, rare) Not to mention, as well as; used after one item, to introduce a further item which is entailed by the first.

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verb

To leave alone, let be; to stop bothering.

I wish he would let me alone so I could get some sleep.

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