Definition of maser
: a device or object that emits coherent microwave radiation produced by the natural oscillations of atoms or molecules between energy levels
Recent Examples of maser from the Web
The maser–the conceptual predecessor to the laser, which had been invented by Townes and others–had been around since the early 1950s, and the theoretical plans for the laser had also been around for a few years.
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Origin and Etymology of maser
microwave amplification by stimulated emission of radiation
First Known Use: 1955See Words from the same year
Medical Definition of maser
: 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
Seen and Heard
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