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[as-troh-fiz-iks] /ˌæs troʊˈfɪz ɪks/
noun, (used with a singular verb)
the branch of astronomy that deals with the physical properties of celestial bodies and with the interaction between matter and radiation in the interior of celestial bodies and in interstellar space.
Origin of astrophysics
First recorded in 1885-90; astro- + physics
Related forms
astrophysical, adjective
[as-troh-fiz-uh-sist] /ˌæs troʊˈfɪz ə sɪst/ (Show IPA),
noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for astrophysicist
Contemporary Examples
Historical Examples
  • Chances were there was no astrophysicist nearer than Ganymede.

    Rip Foster in Ride the Gray Planet

    Harold Leland Goodwin
  • If Mars were incandescent, we should appeal to the astrophysicist for information2 regarding its chemical composition.

    Mars and its Mystery Edward Sylvester Morse
  • The astrophysicist continued, at considerable length, to establish the position of Ceti II to his own complete satisfaction.

    Eight Keys to Eden Mark Irvin Clifton
British Dictionary definitions for astrophysicist


(functioning as sing) the branch of physics concerned with the physical and chemical properties, origin, and evolution of the celestial bodies
Derived Forms
astrophysical, adjective
astrophysicist, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for astrophysicist

1869, usually hyphenated at first, from astro- + physicist. Astrophysics is recorded from 1877.

Online Etymology Dictionary, © 2010 Douglas Harper
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astrophysicist in Science
The branch of astronomy that deals with the physical and chemical processes that occur in stars, galaxies, and interstellar space. Astrophysics deals with the structure and evolution of stars, the properties of interstellar space and its interactions with systems of stars, and with the structure and dynamics of clusters of stars such as galaxies.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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astrophysicist in Culture

astrophysics definition

The branch of astronomy devoted to the study of the physical characteristics and composition of objects in the sky. Typical concerns of astrophysics are how much light the stars give off and the size, mass, and temperature of planets and stars.

The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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