Murphy's Law

noun

: an observation: anything that can go wrong will go wrong

Word History

Etymology

probably from Edward A. Murphy †1990 American engineer

First Known Use

1951, in the meaning defined above

Time Traveler

The first known use of Murphy's Law was in 1951

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Style

“Murphy's Law.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Murphy%27s%20Law. Accessed 25 Jul. 2025.

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Kids Definition

Murphy's Law

noun

Mur·phy's Law

ˈmər-fēz-

: an observation that anything that can go wrong will go wrong

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Murphy's Law

noun

Word History

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Kids Definition