qubit

noun

qu·​bit ˈkyü-bət How to pronounce qubit (audio)
plural qubits
: a unit of computing information that is represented by a state of an atom or elementary particle (such as the spin) and can store multiple values at once due to the principles of quantum mechanics
And the most basic truth of quantum mechanics dictates that you cannot measure a qubit without destroying the superposition. The register that said 1 and 0 will randomly collapse into 1 or 0.George Johnson
compare bit entry 3 sense 1

Examples of qubit in a Sentence

Recent Examples on the Web
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Even just a decade ago, the most advanced quantum systems could only manage five to 10 qubits and were used primarily as research projects. Chris Schueler, Forbes.com, 21 May 2025 Instead of processing data in the binary state of zeros and ones, quantum computers run on qubits, which encompass myriad states all at once. ArsTechnica, 20 May 2025 If one qubit is changed, the other changes instantly. Kurt Knutsson, Cyberguy Report, FOXNews.com, 14 Apr. 2025 These qubits can then basically communicate with each other to further increase the speed and complexity of information processing in a calculation. Rachel Curry, CNBC, 6 Apr. 2025 See All Example Sentences for qubit

Word History

Etymology

qu- (in quantum entry 2) + bit entry 4, probably formed with punning allusion to cubit

Note: According to the American physicist Benjamin Schumacher, in the acknowledgements to a paper ("Quantum coding," Physical Review A, vol. 51, issue 4 [April, 1995], p. 2747), "The term 'qubit' was coined in jest during one of the author's many intriguing and valuable conversations with W. K. Wootters, and became the initial impetus for this work."

First Known Use

1994, in the meaning defined above

Time Traveler
The first known use of qubit was in 1994

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Cite this Entry

“Qubit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/qubit. Accessed 29 May. 2025.

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