Murphy's Law

American  

noun

1. the facetious proposition that if something can go wrong, it will.

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Murphy's law British  

noun

1. informal another term for Sod's law

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Murphy's Law Cultural  

1. A rule that states, “If something can go wrong, it will.” An addition to this law reads, “and usually at the worst time.” The identity of “Murphy” is unknown, but the saying was first used during the 1940s and may have originated with members of the armed forces in World War II.

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Murphy's law Idioms  

1. If anything can go wrong, it will, as in We may think we've covered all the details for the benefit, but remember Murphy's law. The identity of Murphy, if ever a real person, is unknown. Some think it alludes to (but was not invented by) a feckless Irishman named Murphy. [c. 1940]

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Etymology

Origin of Murphy's Law

An Americanism dating to 1950–55; named after Edward A. Murphy, Jr., (1918–90), an American aerospace engineer who worked on safety systems

Example Sentences

But you know what Murphy’s Law says.

From Salon

For James Drescher of Murphy’s Law, playing on Hilly’s Stage was a powerful reminder of the man who gave him and countless others their start.

From Los Angeles Times

Hilly’s Stage was also the scene of a powerful moment when D-Generation’s Jesse Malin, who is recovering from a spinal stroke, rose from his wheelchair and sang alongside Drescher and Murphy’s Law.

From Los Angeles Times

Byrne stars as Linda, a woman looking Murphy’s Law dead in the eye and screaming in its face.

From Salon

Sampson called the final two minutes of regulation “Murphy’s Law,” with missed free throws and the ball bouncing everywhere.

From Seattle Times