slippery slope

American  

noun

1. a dangerous and irreversible course.

   the slippery slope from narcotics to prison.

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slippery slope Idioms  

1. A dangerous course, one that leads easily to catastrophe, as in He's on a slippery slope, compromising his values to please both the bosses and the union. This metaphoric expression alludes to traversing a slick hillside, in constant danger of falling. [Mid-1900s]

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Etymology

Origin of slippery slope

First recorded in 1985–90

Example Sentences

That’s a complex and slippery slope.

From Los Angeles Times

But surrender is a slippery slope.

From Salon

Admittedly, answering emails on the weekend can be a slippery slope.

From MarketWatch

This "slippery slope" argument has been repeatedly raised during debates at Holyrood.

From BBC

Another practical argument against the bill has been concerns about a "slippery slope", with campaigners pointing to Belgium and Canada where assisted deaths have risen as eligibility criteria have expanded.

From BBC