circuit breaker

American  

[sur-kit brey-ker] / ˈsɜr kɪt ˌbreɪ kər /

noun

1. Also called breaker.  Electricity. a device for interrupting an electric circuit to prevent excessive current, as that caused by a short circuit, from damaging the apparatus in the circuit or from causing a fire.

2. Also called trading halt or trading curb.  Stock Exchange. a temporary halt in trading automatically imposed when stock prices reach a predetermined level, as to check panic selling.

3. a lockdown or set of tight restrictions imposed for a fixed, usually short period to halt the spread of a highly transmissible infection (often used attributively).

   Circuit breakers only succeed if additional measures are taken, such as contact tracing and increased testing.

4. Australia, New Zealand. an activity serving to relieve or distract from stresses that might otherwise overwhelm.

   Sometimes a day out of the office is the best circuit breaker after a tense week.

5. any property-tax relief measure that reduces or limits property taxes for certain eligible taxpayers, as those with low income or the elderly.

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circuit breaker British  

noun

1. Sometimes shortened to: breaker.  a device that under abnormal conditions, such as a short circuit, interrupts the flow of current in an electrical circuit Compare fuse 2

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circuit breaker Scientific  

1. A switch that automatically interrupts the flow of electric current if the current exceeds a preset limit, measured in amperes. Circuit breakers are used most often as a safety precaution where excessive current through a circuit could be hazardous. Unlike fuses, they can usually be reset and reused.

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Etymology

Origin of circuit breaker

An Americanism dating back to 1870–75

Example Sentences

"Notwithstanding the imposition of circuit breaker restrictions, the decision-making in Northern Ireland was chaotic," it said.

From BBC

Both Wales and Northern Ireland put in place versions of a circuit breaker lockdown, while in Scotland stricter rules are imposed in the central belt.

From BBC

Despite the use of safeguards such as so-called circuit breakers, which halt trading in volatile issues, flash crashes have since hit markets in other nations and asset classes.

From The Wall Street Journal

Homeowners with electric panels that are several decades old should consider taking advantage of the tax credit, especially if their panelboards support less than 100 amps and use fuses instead of circuit breakers, he says.

From The Wall Street Journal

“Two were related to routine maintenance in port. Two were unexpected tripping of circuit breakers on the accident voyage,” National Transportation Safety Board Jennifer Homendy testified.

From Seattle Times