safety valve

American  

noun

1. a device that, when actuated by a gas or vapor pressure above a predetermined level, opens and allows the gas or vapor to escape until its pressure is reduced to a pressure equal to or below that of the predetermined level.

2. a harmless outlet for emotion, tension, etc.

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safety valve British  

noun

1. a valve in a pressure vessel that allows fluid to escape when a predetermined level of pressure has been reached

2. a harmless outlet for emotion, energy, tension, etc

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Etymology

Origin of safety valve

First recorded in 1805–15

Example Sentences

In addition, they note that now, parents will still have access to the debt, but thanks to the changes to repayment, they won’t have much of a safety valve if it becomes unmanageable.

From MarketWatch • Jul. 1, 2026

And bonds aren’t serving as much of a safety valve, falling in price amid jitters about a rise in inflation.

From The Wall Street Journal • Mar. 14, 2026

Dot plots and macro projections serve as a pressure safety valve where disagreement can be hashed out, without harming the consistency of the policy message.

From Barron's • Dec. 12, 2025

In that incident, the board’s investigation found multiple safety failures, including a severely eroded safety valve that allowed flammable gases to dangerously seep into unwanted areas.

From Los Angeles Times • Oct. 4, 2025

When pressure in the reactor gets too high, a safety valve opens and allows steam to escape into the torus, where it condenses back into water.

From "Meltdown" by Deirdre Langeland