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

Example Sentences

Recent Examples on the Web Previous theories suggested that Mars’ moons formed out of debris ejected when a giant impactor struck Mars between 100 million and 800 million years after the planet's creation. Caitlyn Buongiorno, Discover Magazine, 2 June 2020 Chandrayaan-1 explored the moon in 2008, sending down an impactor to crash on the lunar south pole and fling up dust for investigation. Korey Haynes, Discover Magazine, 31 Dec. 2019 This includes determining the size of the impactor spacecraft and estimating the amount of lead time necessary to ensure that a small deflection would move a potentially dangerous asteroid off its path. Ariana Garcia, Chron, 19 Dec. 2022 As for how this years-long process of impactor detective work got started? Bruce Dorminey, Forbes, 8 Oct. 2022 The goal of the test was to see how well a kinetic impactor would work at changing an asteroid’s orbit and trajectory. Joshua Hawkins, BGR, 27 Sep. 2022 The walls of the crater indicate that the impactor arrived at a considerable angle. John Timmer, Ars Technica, 27 Oct. 2022 Can anything yet be determined about the original size of the impactor? Bruce Dorminey, Forbes, 8 Oct. 2022 The Chicxulub impactor, which left a nearly 100 mile-wide crater off the coast of Mexico some 66 million years ago, wreaked havoc on Earth’s environment and killed off nearly three-fourths of its plant and animal species. Cory Oldweiler,, 6 Oct. 2022 See More

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.

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 31 Jan. 2023.

Last Updated: - Updated example sentences
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