Definition of "laser" []

• Any of several devices that emit highly amplified and coherent radiation of one or more discrete frequencies. One of the most common lasers makes use of atoms in a metastable energy state that, as they decay to a lower energy level, stimulate others to decay, resulting in a cascade of emitted radiation. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Each ball bearing had his name laser etched on it."
• "The term laser radar is also in use but is misleading because it uses laser light and not the radiowaves that are the basis of conventional radar"
• "Nov. 9, 1957: Columbia grad student Gordon Gould writes in his notebook calculations for what he calls a laser Light Amplification by Stimulated Emission of Radiation."