absolute zero


: a theoretical temperature characterized by complete absence of heat and motion and equivalent to exactly −273.15°C or −459.67°F

Examples of absolute zero in a Sentence

Recent Examples on the Web In 1990, the Cosmic Background Explorer satellite, or COBE, reported that the temperature of the microwave background was a consistent 2.7 kelvin — 2.7 degrees Celsius above absolute zero — in every direction. Dennis Overbye Hiroko Masuike, New York Times, 4 Sep. 2023 This millennia-long delay, in part, was because humans had no way of simulating temperatures approaching absolute zero, or -459.67 degrees Fahrenheit. Darren Orf, Popular Mechanics, 15 Aug. 2023 These near-microscopic, aquatic extremophiles can survive in the most inhospitable places on Earth, including frigid absolute zero temperatures, boiling hot hydrothermal vents, a vacuum of space, and pressure six times more crushing than the deep ocean, per National Geographic. Rachael Lallensack, Smithsonian Magazine, 29 Dec. 2021 The catch here is that deleting information from a particle is the exact same thing as taking that particle to absolute zero. Jackie Appel, Popular Mechanics, 4 May 2023 The lab space includes deep refrigeration equipment that can reach temperatures just a fraction of a degree above absolute zero, or minus-460 degrees Fahrenheit — the point at which all atomic movement ceases. Aaron Pressman, BostonGlobe.com, 29 June 2023 That includes withstanding the crushing pressure of the ocean floor, the DNA-shredding powers of radiation, temperatures just one degree above absolute zero (the temperature at which molecular motion ceases), and even the vacuum of space. Kate Golembiewski, Discover Magazine, 8 June 2023 Researchers just found a new way to get an object to absolute zero. Jackie Appel, Popular Mechanics, 4 May 2023 These atoms can be cooled close to absolute zero in a lattice grid of laser light, reducing noise and improving timing stability. Paul Lipman, Forbes, 27 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'absolute zero.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1798, in the meaning defined above

Time Traveler
The first known use of absolute zero was in 1798

Dictionary Entries Near absolute zero

Cite this Entry

“Absolute zero.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/absolute%20zero. Accessed 25 Sep. 2023.

Kids Definition

absolute zero

: a hypothetical temperature that has never been reached, represents no heat at all, and is equal to approximately −273.15°C or −459.67°F

Medical Definition

absolute zero

: a theoretical temperature characterized by complete absence of heat and equivalent to exactly −273.15°C or −459.67°F

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