sheet anchor

American  

noun

1. Nautical.  a large anchor used only in cases of emergency.

2. a final reliance or resource, as when in danger.

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sheet anchor British  

noun

1. nautical a large strong anchor for use in emergency

2. a person or thing to be relied upon in an emergency

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Etymology

Origin of sheet anchor

First recorded in 1485–95

Example Sentences

Pinning points form when part of a floating ice sheet anchors itself to an elevation on the ocean floor, creating a visible bump on the otherwise smooth ice shelf surface.

From Science Daily

Yet, Jane — Tomalin calls her “the true heroine of this story” — remained the sheet anchor of his life, as well as his typist.

From Washington Post

But to Abraham Lincoln, these principles were “the sheet anchor of American republicanism.”

From Salon

The feels "the world has enough problems without losing the surety of its sole superpower, the country which despite its faults remains the sheet anchor for the world's security and economy".

From BBC

They have a number of policy levers they can utilize or balance sheet anchors that represent dry powder to withstand market volatility.

From Reuters