phys·​ics | \ˈfi-ziks \

Definition of physics 

1 : a science that deals with matter and energy and their interactions

2a : the physical processes and phenomena of a particular system

b : the physical properties and composition of something

Examples of physics in a Sentence

Recent Examples on the Web

Stewart, Friedman and their colleagues are in the research group of cosmologist Philip Lubin, a professor of physics at the University of California, Santa Barbara, who has a lot of space-laser experience. Mike Wall,, "Student Project Scans Sky for Alien Laser Beams," 29 Sep. 2018 The first foray into this poop-tastic piece of physics happened during the '50s, with a particularly groundbreaking (and skin-crawling) piece of research emerging in 1975, when Charles P. Gerba published a study in the journal Applied Microbiology. Caroline Picard, Good Housekeeping, "Please, for the Love of God, Close the Toilet Lid When You Flush," 20 Aug. 2018 To win, hoist an uncooperative toddler in the air the most times without breaking your back or any laws of physics. James Breakwell, Indianapolis Star, "Xploding Unicorn: Parenting Olympics would judge you with cold, hard numbers," 4 Apr. 2018 Barry Garraway, a professor of quantum physics at the University of Sussex in the England who is not involved with CAL, said in an email. Denise Chow /, NBC News, "Space station experiment will create the coldest spot in the universe," 22 June 2018 As Pletcher describes it, the multidirectional road to the Derby is not exactly quantum physics. Childs Walker,, "Like the sun rising in the East, Todd Pletcher is back with four Kentucky Derby contenders," 2 May 2018 But no matter how perfect one’s knowledge of conditions may be, since quantum physics seems to propose existence exhibits true randomness, perhaps even an omniscient God cannot fully know. Rabbi David Wolpe, Time, "Why We Shouldn't Be So Sure of Our Predictions About the Future," 20 Apr. 2018 Mathematical physicist and cosmologist Stephen Hawking was best known for his work exploring the relationship between black holes and quantum physics. Christoph Adami, Newsweek, "How Stephen Hawking's Black Hole Discoveries Rewrote Physics of Space-Time," 19 Mar. 2018 An anesthesiologist develops a fringe theory about quantum physics and consciousness. Discover Magazine, "Table of Contents March 2018," 9 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'physics.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of physics

1715, in the meaning defined at sense 1

History and Etymology for physics

Latin physica, plural, natural science, from Greek physika, from neuter plural of physikos of nature, from physis growth, nature, from phyein to bring forth — more at be

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Statistics for physics

Last Updated

21 Nov 2018

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Time Traveler for physics

The first known use of physics was in 1715

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More Definitions for physics



English Language Learners Definition of physics

: a science that deals with matter and energy and the way they act on each other in heat, light, electricity, and sound


phys·​ics | \ˈfi-ziks \

Kids Definition of physics

: a science that deals with the facts about matter and motion and includes the subjects of mechanics, heat, light, electricity, sound, and the atomic nucleus

phys·​ics | \ˈfiz-iks \

Medical Definition of physics 

: a science that deals with matter and energy and their interactions in the fields of mechanics, acoustics, optics, heat, electricity, magnetism, radiation, atomic structure, and nuclear phenomena

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More from Merriam-Webster on physics

Spanish Central: Translation of physics

Nglish: Translation of physics for Spanish Speakers

Britannica English: Translation of physics for Arabic Speakers Encyclopedia article about physics

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