im·​pac·​tor | \im-ˈpak-tər \
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

So even though the impactor loses its water, some of it is recaptured as the melt rapidly quenches. Jay Bennett, Popular Mechanics, "NASA's High-Speed Cannon Used to Explore the Origins of Water on Earth," 26 Apr. 2018 This goes against previous studies that suggested a much larger impactor. John Wenz, Popular Mechanics, "New Study Explains the Solar System Smash-Up That Created Mars' Two Moons," 18 Apr. 2018 In short-warning scenarios, kinetic impactors like DART would not be enough. NBC News, "Space scientists have big plans to avert an asteroid apocalypse," 6 Apr. 2018 Given enough warning, less complicated options like a kinetic impactor might be preferable. Popular Mechanics, "The Asteroid Hunters," 11 Nov. 2015 The asteroid that wiped out the dinosaurs 65 million years ago measured about 10 kilometers wide, but any impactor larger than 1 kilometer wide could trigger catastrophic climate change. Eoin O'carroll, The Christian Science Monitor, "Buzzworthy space rocks: Asteroid hunters prep for near miss," 10 Oct. 2017 Scientists are already working on ways to deflect potential impactors. Eoin O'carroll, The Christian Science Monitor, "Buzzworthy space rocks: Asteroid hunters prep for near miss," 10 Oct. 2017 That's exactly what the Double Asteroid Redirection Test (DART) impactor spacecraft would do. Jay Bennett, Popular Mechanics, "NASA Spacecraft Would Smash Into an Asteroid as a Dry Run for Saving the Planet," 3 July 2017

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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Time Traveler for impactor

The first known use of impactor was in 1872

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