maser

noun

ma·​ser ˈmā-zər How to pronounce maser (audio)
: a device or object that emits coherent microwave radiation produced by the natural oscillations of atoms or molecules between energy levels

Examples of maser in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In fact, observations of these masers have proved that our Milky Way is a magnificent example of a spiral galaxy. — Phil Plait, Scientific American, 20 Feb. 2025 Atomic clocks, including hydrogen masers and cesium beam clocks, rely on the natural resonant frequencies of atoms to tell time with extremely high accuracy. — Joe Hernandez, NPR, 21 Dec. 2025 In 1960, physicist Ted Maiman developed the laser by building on its 1950s predecessor, the maser. — John Ballato, The Conversation, 24 Mar. 2026 The observatory’s central building—a one-story structure housing workshops, desks, racks of processors, and a maser used to distribute clock signals to the telescopes—is completely wrapped in a continuous steel sheet. — IEEE Spectrum, 28 Nov. 2017 Those applications include satellite technology, masers, microwave photon detection, hunting for axions (a dark matter candidate), and various quantum systems, and driving spin in superconducting qubits for quantum computing, among others. — Jennifer Ouellette, Ars Technica, 27 Dec. 2024

Word History

Etymology

microwave amplification by stimulated emission of radiation

First Known Use

1955, in the meaning defined above

Time Traveler
The first known use of maser was in 1955

Rhymes for maser

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Browse Nearby Words

Masefield
maser
Maseru
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Cite this Entry

“Maser.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/maser. Accessed 7 Jul. 2026.

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Kids Definition

maser

noun
ma·​ser ˈmā-zər How to pronounce maser (audio)
: a device that uses the natural vibrations of atoms or molecules for generating electromagnetic radiation at a single microwave frequency

Medical Definition

maser

noun
ma·​ser ˈmā-zər How to pronounce maser (audio)
: a device that utilizes the natural oscillations of atoms or molecules between energy levels for generating electromagnetic radiation in the microwave region of the spectrum

More from Merriam-Webster on maser

Britannica.com: Encyclopedia article about maser

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