im·​pac·​tor im-ˈpak-tər How to pronounce impactor (audio)
variants or impacter
: a machine (such as a steam or air hammer or a pile driver) or part that operates by striking blows

Examples of impactor in a Sentence

Recent Examples on the Web The impactor that formed the Moon, on the other hand, may have been about the size of Mars. Alka Tripathy-Lang, Ars Technica, 26 Jan. 2024 The software has been validated by replicating other impacts, including when Japan’s Hayabusa2 spacecraft punched a small copper impactor into the Ryugu asteroid in 2019. Ashley Strickland, CNN, 27 Feb. 2024 An impactor the size of the 20-meter-wide space rock that broke up over Chelyabinsk, Russia in February 2013 could be intercepted a mere 100 seconds prior to impact, whereas one the size of the Tunguska impactor (50 meters in diameter) would require interception some five hours prior to impact. Scientific American, 13 Oct. 2021 The smallest impactors considered in this model have a diameter of 15 kilometers. Alka Tripathy-Lang, Ars Technica, 26 Jan. 2024 Crunch time The process of building a planet necessarily generates a lot of heat as impactors of various sizes deliver both matter and energy to the growing planet. John Timmer, Ars Technica, 3 Oct. 2023 The impactors—six-foot-long, six-inch-thick rods filled with explosives—would smash into the asteroid like buckshot, efficiently dismantling it. Popular Science, 1 Nov. 2023 Spring: Roads are a key impactor for wildlife around the world. Chris Klimek, Smithsonian Magazine, 21 Dec. 2023 An appropriately-sized impactor could turn an asteroid into a shower of rubble (Credit: The results suggest that these impacts turn both asteroids into fragments, many of which would hen rain down on Earth. Discover Magazine, 30 Oct. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'impactor.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1872, in the meaning defined at sense 1

Time Traveler
The first known use of impactor was in 1872

Dictionary Entries Near impactor

Cite this Entry

“Impactor.” Dictionary, Merriam-Webster, Accessed 23 Apr. 2024.

Last Updated: - Updated example sentences
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