im·​pac·​tor | \ im-ˈpak-tər How to pronounce impactor (audio) \
variants: or impacter

Definition of impactor

1 : a machine (such as a steam or air hammer or a pile driver) or part that operates by striking blows
2 : meteorite

Examples of impactor in a Sentence

Recent Examples on the Web And why reinvent the Chicxulub impactor wheel when asteroid impactors might work after all? Bruce Dorminey, Forbes, 28 Feb. 2021 The energy that must have been deposited by an impactor to cause the formation of Chicxulub crater. Ethan Siegel, Forbes, 18 May 2021 Nevertheless, the impactor may have triggered a series of unfortunate events because the planet was already in a fragile state. She En Kim, Smithsonian Magazine, 18 June 2021 For decades, scientists argued over whether the impactor was an asteroid or a comet, with the data overwhelmingly favoring asteroids. Ethan Siegel, Forbes, 18 May 2021 The scientists also considered the use of nuclear explosives to destroy or at least severely reduce the odds of any large impactor being able to pass through Earth’s atmosphere. Mike Wehner, BGR, 3 May 2021 But whereas a hammer swing delivers approximately 0.0001 kilojoules of energy, the Chicxulub impactor delivers approximately 1,300,000,000,000,000,000,000,000. Cody Cassidy, Wired, 9 Apr. 2021 The theory invoked an impactor the size of Mars or—in recent variants—much smaller. Paul Voosen, Science | AAAS, 23 Mar. 2021 But based on new isotopic evidence and modeling, Yuan believes the LLSVPs are the guts of the alien impactor itself. Paul Voosen, Science | AAAS, 23 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'impactor.' 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 impactor

1872, in the meaning defined at sense 1

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The first known use of impactor was in 1872

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impact parameter

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Last Updated

17 Sep 2021

Cite this Entry

“Impactor.” Dictionary, Merriam-Webster, Accessed 27 Sep. 2021.

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